木材干燥应力连续监测方法的研究

本文在卡普法的基础上，提出了木材干燥应力连续监测方法，并设计了所需的配套装置。该方法采用涡流传感器对干燥过程中卡普片的矢高进行连续测试，同时通过计算机自动采集、存储数据。结果表明：矢高与干燥时间存在精密的相关性，它们之间的相关系数大部分达到0．99以上，从而实现了木材干燥应力的自动与连续监测。     

杜仲研究的历史,现状和展望

本文讨论了杜仲研究的历史和现状，并根据现在研究的成果和存在的问题，对将来应该开展的研究课题提出了一些建议。     

广义连续格的结构

以上（下）子格为工具建立广义连续格的诸结构定理，它们奠定这些格的完全链表现的基础。     

Application of acoustic Doppler current profiler combined with a scientific echo sounder for krill Euphausia pacifica density estimation

ABSTRACT:   An application of the acoustic Doppler current profiler (ADCP, 153.6 kHz) in combination with a scientific echo sounder (EK60, 38 and 200 kHz) was investigated to estimate the density of krill Euphausia pacifica . The acoustic backscattering strength from sound scattering layers was compared with biomass estimates from midwater trawls. Euphausia pacifica was targeted among mixed species populations in the sound scattering layer in the offshore Funka Bay area of Hokkaido, Japan. The frequency characteristics of acoustic backscattering by krill were calculated using a distorted wave Born approximation scattering model at three frequencies. Krill aggregations identified from the EK60 data were extracted as the mean volume backscattering strength difference between two frequencies. They were then used to identify similar aggregations in the ADCP data by matching observation times and depths for the two methods, which were applied simultaneously. Results from the comparison of the mean volume backscattering strength and the density calculated from the ADCP and EK60 showed that ADCP can be used to measure density and spatial–temporal distribution of krill aggregations. Current speed and direction at the study site were found to be 16.1 cm/s and 187.0°, respectively, and krill speed and direction (including the current component) were found to be 19.8 cm/s and 172.2°, respectively. Based on the ADCP data, the net speed and direction of the krill aggregations were found to be 5.9 cm/s and 128.0°, respectively.     

微波电路电测及其计算方法

从实际工程的角度出发，对电路电测方法进行了论述。在微通信工程中，需要获得障碍物的位置和高度，最合理的天线高度组合和障碍物绕射损耗等参数，为此论述了微波电路电测方法及技术要求。在大庆－秦皇岛输油管道通信工程中采用了Ａ，Ｂ测试法进行测试，得到高度－损耗曲线。这种曲线给出相对自由空间接收电平与收，发天线高度之间的关系。在测试所得的高度－损耗曲线与断面图相结合的基础上，由绕射损耗计算公式推出了几种常见障碍     

继电保护用电流互感器的暂态特性数字仿真及电磁优化设计

本文在分析CT的暂态特性及其动态磁化过程的基础上,建立了计及铁芯饱和、局部磁滞回环、动态剩磁影响的CT单、复励磁暂态过程数字仿真模型,提出了继电保护用P、TPX、TPY、TPz级CT的电磁优化设计方法,编制了计算机程序,用于CT的电磁优化设计及数字仿真分析.     

水稻机械化喷直播技术的应用现状及对策

分析了水稻机械化喷直播技术的特点和技术要求，介绍了水稻机械化喷直播技术的应用现状及其技术推广的制约因素．提出了推广水稻机械化喷直播技术的对策．     

湖南马尾松遗传改良现状与策略

在叙述湖南马尾松20多年来于马尾松群体遗传改良、马尾松优良家系定向选择、马尾松基因资源收集与种子园营建等方面所取得成绩的基础上，探讨了目前马尾松遗传改良所存在的问题，提出了今后一段时期湖南马尾松遗传改良策略。     

油罐阻油切水阀启动过程的研究

本文对油罐本安型阻油切水阀研制过程中的几个技术关键之一￣二次启动进行了较详细的力学分析，研究了阻油切水阀的启动过程，分析了启动过程中液体在静止和流动两种情况下对浮球工作的影响，提出了启动机构方案。     

Weeding techniques in transplanted and direct wet-seeded rice in Pakistan

Field studies were undertaken to explore the weed management strategies for transplanted and direct wet-seeded rice in the Dera Ismail Khan district of North-west Frontier Province, Pakistan. The experimental design was a randomized complete block with a split plot arrangement. The main plots consisted of two planting techniques (transplantation and direct seeding), while weed control practises assigned to the subplots included the use of the granular herbicide Sunstar 15WG (ethoxy sulfuron), Machete 60EC (butachlor), conventional hand weeding, and the weedy check (untreated control). Data were recorded on weed dynamics and the agronomic parameters of the rice crop. Economic analyses on the data were also run. The weed density and biomass were lower in the transplantation plots than the direct-seeding plots. The herbicides ethoxy sulfuron and butachlor reduced the density over the weedy check, with a density comparable to hand weeding in 2002, but slightly higher in 2003. As a result of weed management by hand weeding and herbicides, the paddy yield and its components were significantly higher for the transplanted method compared to the direct-seeded method. The comparable yield of herbicides with hand weeding offers an option for the use of herbicides as an alternative management tool. In light of our findings, it is concluded that for good economic returns, rice crops may be transplanted rather than direct-seeded. The herbicides ethoxy sulfuron and butachlor offer a weed control cover comparable with hand weeding under the transplantation method, while butachlor is good for controlling weeds even under the direct-seeded conditions in the agroclimatic conditions of the area.