民用飞机需求确认流程研究

基于需求的民用飞机研发是按照系统工程的思想,以利益相关方需求为出发点开展复杂产品的设计工作。需求确认作为系统工程的重要活动,目的是为了保证需求的正确性和完整性。本文根据SAE ARP4754A的要求并结合实际工程经验,定义了一套较为适用的民用飞机需求确认流程,用以指导民机设计人员开展实际的需求确认工作。     

民用飞机系统需求确认流程方案研究

需求是民机设计的源头,在民机设计流程中至关重要。需求确认旨在以通过控制流程的方式来证明所捕获的需求的正确性和完整性。本文讨论了需求确认流程的特点,并提出了一种基于ARP 4754A的针对民用飞机系统的需求确认流程方案。     

HWIL硬件在环仿真方法在民机刹车系统中的应用介绍

本文针对安全性要求非常高的民机刹车系统,介绍了验证其性能和排故等的一个比较先进的方法——HWIL硬件在环仿真方法,给出了HWIL刹车试验平台搭建方法,比较了HWIL相对于传统方法的优势。最后,提供了刹车系统使用HWIL进行仿真试验的具体考虑。通过介绍可以看出,HWIL方法对于民机刹车系统研制具有重要作用。     

民用飞机蓄压器供压刹车浅析

本文介绍了ERJ190、A320、B737飞机液压能源系统失效情况下的刹车设计特点,比较分析了某民机蓄压器供压时应急刹车和正常刹车的工作特性,给出了飞行员操作建议,供其它民机刹车研制参考。     

民用飞机电源系统安全性评估(SSA)研究

本文对民用飞机的电源系统安全性评估工作进行了介绍,结合SAE ARP4761的要求和电源系统的研制特点,归纳总结了安全性评估流程。     

民机刹车效率计算方法研究

总结了民机适航中对防滑刹车系统效率的要求,分析研究了湿跑道刹车效率计算方法 ,以某型飞机为例使用真实湿跑道试验数据进行计算,为其它民机的湿跑道刹车效率计算提供参考。     

民机系统研制中关于限制研制错误的考虑

本文针对民机综合复杂系统研制中出现研制错误的风险,阐述了目前工业界在限制研制错误方面取得良好实施效果的实践方法,包括研制保证过程与架构减缓等方面,在此基础上总结了对于我国民机系统研制的相关启示。     

民用飞机研制问题管理实践与体会

民用飞机研制是一项高度复杂的系统工程,为了满足民机适航规章条款要求,需要开展大量的符合性验证工作,由于各种因素会出现影响项目研制的一些问题,如何第一时间发现问题、分析问题直至解决问题,确保项目研制成功,是民机研制项目管理中的重点之一。通过对民机研制问题管理全过程的分析和说明,阐述了民机研制问题管理的方法和重要性,对我国民机研制问题管理工作具有一定的指导作用。     

民机液压系统压力测点改装技术探讨

民机液压系统在研制取证过程中需要对系统重要的压力参数(通常包括压力脉动、压力冲击和背压等)进行测量和分析,以便确定液压系统满足合适的功能和性能设计指标。本文分析了液压压力测点改装的常用方法,从改装需求出发,到详细设计过程和方案实现,系统阐述了液压压力测点改装的关键技术和工作思路,给出了可供相似民机液压系统研制借鉴和参考的方法和流程。     

民机系统研制中的共模分析方法及发展趋势

本文描述了民机系统研制中开展共模分析的一般方法与步骤,随后剖析了随着民机系统的高度综合复杂化,共模分析所遇到的挑战以及可能需要关注的发展方向,同时阐述了适航审查中的难点问题,在上述基础上总结了对于我国民机系统研制的相关启示。     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.     

Mechanism of Action of Probiotic Function of Lactobacilli

乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制.     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …