Effect of dietary cellulose level on specific dynamic action and ammonia excretion of the prawn Macrobrachium rosenbergii (De Man 1879)

The feeding energetics of the prawn Macrobrachium rosenbergii (De Man 1879) were examined with respect to the effect of dietary fibre. Adult animals were fed semi‐purified diets with 0%, 5%, 10% and 15%α‐cellulose to determine the maximum aerobic scope that could be elicited by the increase in metabolism as specific dynamic action (SDA). The excretion rates of ammonia were also measured. Prawns fed all diets had significantly higher respiration rates after feeding due to SDA. Feed intake was not related to metabolism rate. Both oxygen uptake and ammonia excretion were affected by feed intake, dietary cellulose and time after feeding. SDA was related to dietary fibre, indicated by increments varying from 37% to 386%. O:N ratios were influenced by feed intake, dietary cellulose levels and time after feeding. O:N ratios of between 10 and 49 indicate that the prawns predominately metabolize carbohydrate.     

长白山旅游形象价值及旅游传播作用--长白山旅游文化系列研究

分析了休闲旅游业的形象产业属性与价值,探讨了长白山科学文化资源与旅游形象定位,对长白山休闲旅游地旅游形象的传播进行了研究,指出了长白山休闲旅游景区的导游产品及导游服务要成为长白山旅游形象的传播者,以此树立长白山国际休闲旅游名山的科学形象、文化形象、诚信友善的形象,获得满意体验的旅游者是旅游景区形象的最忠实的传播者。     

依托口译技能的跨文化交际能力培养模式及其效果

提高学生的跨文化交际能力可以通过显性路径和隐性路径两种方式.根据口译课程的特点,在口译教学中运用隐性教学方式将跨文化教学内容融入到口译各技能的训练之中是比较科学合理的做法.一项对比教学实验的结果表明,依托口译技能的跨文化交际能力培养模式对提高学生的跨文化敏感度整体水平没有显著促进作用,但是对差异认同感有显著积极影响;实验结果同时表明此教学模式能够显著提高学生的跨文化交际能力测试成绩.相关分析和回归分析结果表明,学生的综合跨文化敏感度和除了差异认同感的其他四个维度对学生的跨文化交际能力测试成绩没有产生显著影响,这说明该教学模式产生了一定的积极效果但还需在教学实践中不断修正以更全面和切实地提高学生的跨文化交际能力.     

移动通信系统中路径损耗的研究

首先在同时考虑两个城市参数的情况下,对一个已存在的经典传播预测模型进行改进优化;然后运用MATLAB软件仿真分析了该模型的路径损耗与各参数的关系,建立了三维立体图,相对于二维图形,它的优势是在一幅图里可以观察到两个城市参数随路径损耗同时变化的情况;最后根据阿克苏与阿拉尔地区的实际地形设置仿真参数,并对其进行仿真分析,仿真结果与理论一致。     

Surface Morphology Investigation of Tunisian Dromedary Hair

In raw materials of dromedary hair, there are two distinct fibre populations： The fine one is of textile relevance and the coarse one is rather worthless and must be as a rule separated prior to spinning and subsequent processing. The fibre surface morphology and fibre fineness of Tunisian dromedary hair has been investigated by means of scanning electron microscope （SEM）. SEM microscopic method provides the fibre diameter, the scale shape, the scale frequency and scale height. The results show that dehaired dromedary fibre presents a relatively low mean fibre diameter （≈ 17 μm） with a high coefficient of variation （CV ≈ 25%）. The scales of the dromedary fibre are on average extremely long and quite visible, they tend not to protrude from the fibre, appear almost convex, and provide a wavy appearance in profile of the relatively coarse fibre. On counting the scale frequency, that is, the number of scale margins within a determined fibre length of 100 μm on the surface of a fine （diameter 〈 30 μm） and coarse （diameter 〉 30 μm） dromedary fibre, comes out roughly five at eight and eight at twelve scale margins, respectively. The mean height of the cuticle scale is 0.12μm and 0.24 μm, respectively, for fine and coarse dromedary fibre. These explain why dromedary fibres present a soft touch due to the prominence of the scale edges. This aspect of the surface structure has a high correlation with the felting capacity of the matter, and contributes to the concepts of handle and gloss.     

浅析3G移动通信技术在农业科技信息传播中的应用

本文介绍了3G移动通信技术的特点,分析了农业科技信息传播中存在的主要问题,从五个方面提出了将3G移动通信技术应用于农业科技信息传播工作的服务方式。     

水稻节水灌溉无线远程PLC监控系统

为了改善传统的水稻灌溉方式中水量、电能消耗大,控制设备功能单一,布线复杂和可靠性不高的问题。设计了一种采用无协议通信方式的水稻节水灌溉无线远程PLC监控系统,系统由主站和子站组成。主站向子站发送命令,子站接收后采集传感器数据和电磁阀状态并上传,主站对数据进行存储和显示。同时,根据需求设计了系统的总体结构、硬件结构和软件流程图。实际应用表明,该系统工作稳定,在节水节能的同时使水稻获得优质增产的良好效果。     

Research on the improvement of the convergencespeed for CDMA system power control

Optimal power control with game-theory has been a hot research topic in code division multiple access (CDMA) system. However, the convergence speed of the power control algorithm based on traditional static game-theory is not fast enough and the power fluctuation is large during the iterative process. In order to solve this problem, dynamic game-theory is introduced into CDMA system power control algorithm. The simulation results show that the proposed algorithm, compared with the distributed power control algorithm based on the traditional static game theory, can improve the convergence speed obviously with the same power spending.     

茶园信息采集无线传感器网络节点设计

针对茶园中所存在的无线通信障碍问题,该文设计了一款适合茶园信息采集的无线传感器网络节点。节点以ATmega128为核心,nRF905射频芯片及其外围电路作为无线通信模块,SHT11空气温湿度传感器和TDR-3土壤含水量传感器及其外围电路作为传感器模块,并以该节点为硬件平台编写了通信协议、应用程序和后台管理软件。分析、测试了节点的功耗和通信距离,在空旷地带,节点的有效通信距离达到150 m,与Micaz节点对比室内外通信距离分别提高了200%和150%。在广东省英德茶园基地进行了组网试验测试,结果表明：网络平均丢包率为0.84%,传感器感知精度达到98.2%,能够满足茶园信息采集的应用要求。