浅谈开放式数控系统及其在线切割机床上的应用

介绍了开放式体系结构数控系统的概念、特点及分类,并简要介绍了开放式数控系统在电火花线切割机上的应用。     

A multi-analysis approach for space–time and economic evaluation of risks related with livestock diseases: The example of FMD in Peru

This study presents a multi-disciplinary decision-support tool, which integrates geo-statistics, social network analysis (SNA), spatial-stochastic spread model, economic analysis and mapping/visualization capabilities for the evaluation of the sanitary and socio-economic impact of livestock diseases under diverse epidemiologic scenarios. We illustrate the applicability of this tool using foot-and-mouth disease (FMD) in Peru as an example. The approach consisted on a flexible, multistep process that may be easily adapted based on data availability. The first module (mI) uses a geo-statistical approach for the estimation (if needed) of the distribution and abundance of susceptible population (in the example here, cattle, swine, sheep, goats, and camelids) at farm-level in the region or country of interest (Peru). The second module (mII) applies SNA for evaluating the farm-to-farm contact patterns and for exploring the structure and frequency of between-farm animal movements as a proxy for potential disease introduction or spread. The third module (mIII) integrates mI–II outputs into a spatial-stochastic model that simulates within- and between-farm FMD-transmission. The economic module (mIV) connects outputs from mI–III to provide an estimate of associated direct and indirect costs. A visualization module (mV) is also implemented to graph and map the outputs of module I–IV. After 1000 simulated epidemics, the mean (95% probability interval) number of outbreaks, infected animals, epidemic duration, and direct costs were 37 (1, 1164), 2152 (1, 13, 250), 63 days (0, 442), and US$ 1.2 million (1072, 9.5 million), respectively. Spread of disease was primarily local (<4.5 km), but geolocation and type of index farm strongly influenced the extent and spatial patterns of an epidemic. The approach is intended to support decisions in the last phase of the FMD eradication program in Peru, in particular to inform and support the implementation of risk-based surveillance and livestock insurance systems that may help to prevent and control potential FMD virus incursions into Peru.     

Spatially explicit fisheries simulation models for policy evaluation

This paper deals with the design of modelling tools suitable for investigating the consequences of alternative policies on the dynamics of resources and fisheries, such as the evaluation of marine protected areas (MPA). We first review the numerous models that have been developed for this purpose, and compare them from several standpoints: population modelling, exploitation modelling and management measure modelling. We then present a generic fisheries simulation model, Integration of Spatial Information for FISHeries simulation (ISIS‐Fish). This spatially explicit model allows quantitative policy screening for fisheries with mixed‐species harvests. It may be used to investigate the effects of combined management scenarios including a variety of policies: total allowable catch (TAC), licenses, gear restrictions, MPA, etc. Fisher's response to management may be accounted for by means of decision rules conditioned on population and exploitation parameters. An application to a simple example illustrates the relevance of this kind of tool for policy screening, particularly in the case of mixed fisheries. Finally, the reviewed models and ISIS‐Fish are discussed and confronted in the light of the underlying assumptions and model objectives. In the light of this discussion, we identify desirable features for fisheries simulation models aimed at policy evaluation, and particularly MPA evaluation.     

转盘式对虾开背工艺分析与参数优化

针对目前对虾开背环节工艺不完善、实际应用装备缺乏等问题,以中型南美白对虾为研究对象,探究了对虾开背关键工艺方法,建立了对虾开背过程力学模型,获得影响开背效果主要因素为刀具角度、加工中心盘转速和刀具安置距离;采用单因素试验研究和分析了各因素对开背成功率、虾仁损伤率、虾线裸露成功率和感官评分值的影响,确定影响因素最佳区间为：刀具角度20°~60°、加工中心盘转速10~40r/min和刀具安置距离9~11mm;利用Design-Expert软件进行多因素响应面试验研究分析,并采用多目标优化方法,得到最优参数组合为：刀具角度43.838°、加工中心盘转速28.391r/min、刀具安置距离9.801mm时,开背成功率为99.161%、虾仁损伤率为2.825%、虾线裸露成功率为90.727%、感官评分值为86.944。验证试验结果表明：针对中型南美白对虾,当刀具角度45°、加工中心盘转速28r/min、刀具安置距离9.8mm时,开背成功率为98.89%、虾仁损伤率为3.33%、虾线裸露成功率为87.78%、感官评分值为85.33,与理论优化值的绝对误差均较小,优化后的对虾开背装置性能满足作业要求。研究可为对虾开背工序装置设计和参数选择提供理论基础和科学依据。     

The use of the hand-held infrared thermometer as an early detection tool for exertional heat illness in Thoroughbred racehorses: A study at racetracks in eastern Australia

Thoroughbred racehorses perform exercise at maximal intensities and typically display a hyperthermic exercise response, which can drive core body temperature to critical levels. Despite extremely efficient thermoregulatory mechanisms, certain weather conditions may affect the horse’s ability to cool and result in a syndrome referred to as exertional heat illness (EHI). This is characterised by central nervous system dysfunction, as well as cytotoxic effects of heat on cells, which can produce deleterious consequences. Early detection of exertional heat illness (EHI) in Thoroughbred racehorses can be difficult because signs are often vague and the measurement of rectal temperature as an indicator of hyperthermia is not practical. Best practice in the treatment of EHI in horses, as in human subjects, centres on early detection, rapid assessment and aggressive cooling. Research in human subjects has shown that EHI is manageable when recognised early and appropriate treatment provided. The aim of this study was to investigate the measurement of skin surface temperature (SST) by an infrared thermometer as an aid in the early detection of EHI. A skin surface temperature ≥39°C in the immediate postrace period is considered to be hot. It reflects the interaction of exercise-related metabolic heat production, physiological adjustments to the skin surface such as vasodilation and sweating, together with the effect of high ambient temperature. Most importantly, high SST is associated with a reduced core-to-skin temperature difference, which retards heat transfer from the deep body tissues to the skin and can hinder heat dissipation. Identification of horses with high SSTs can prioritise them for rapid cooling and curtail possible progression to EHI.     

螺纹铣削工艺的选择

总结了在数控加工中心上进行螺纹铣削的一些注意事项,其中包括螺纹铣削刀具的选用及测定、螺纹铣削底径的确定、铣削方式的选择及精度控制等。     

Reliability model for Subsystems of CNC machine tool with small samples

Many subsystems in CNC machine tool have only a few failures, so they are small samples. In this case, classical reliability modeling method often has large errors. For the failure data of small sample, maximum likelihood estimation method is used to estimate the Weibull distribution model parameters of time between failures of the subsystems. Then, the Weibull distribution model parameters are modified by parameter bias correction method. Finally, the effect of bias correction parametersis tested by the D test and the error area ratio test method. The test results show that the modified models are better.     

贵州省数字化生物标本馆的研究与建设

阐述了建立贵州省生物标本信息化标准体系的原则;应用Powerbuilder 9.0作为前端开发工具,并用SQL Server作为服务端开发工具建成了贵州省数字化生物标本馆管理系统和数据库,该系统和数据库至少能存储40万份标本数据;数据录入记录数总计8435条（图像7553幅）,共计130科、382属、1291余种。实现了网上生物标本资源信息发布。并对目前存在的问题进行了出讨论。     

基于人工神经网络的金属切削刀具磨损的识别与控制

根据金属切削刀具磨损与切削力的关系，建立了基于人工神经网络的切削刀具磨损的识别与控制系统，初步实现了用人工神经网络对金属切削刀具磨损的动态识别与控制。     

专家系统在冲压模具初始设计中的应用

提出了专家系统应用于冲压模具初始设计的思路 ,简要介绍了此专家系统的总体结构 ,详尽分析其知识表示方法、知识库结构及推理机的设计。知识表示方法和知识库结构的设计引入面向对象技术和数据库技术 ,推理机用面向对象推理机与面向过程推理机共同实现