PROBABILISTIC STABILITY EVALUATION OF AC/DC POWER SYSTEMS WITH PARALLEL MONTE CARLO METHOD

This paper presents a new method for the probabilistic stability evaluation of AC/DC power systems. The transient stability model is described and the stochastic factors having effects on the stability behaviors are analysed and modeled. A theorem governing the probabilistic relations among the occurences of different types of disturbances is derived. A method of parallel computation is oresented, which is based on Monte Carlo simulation. An illustrative example is also given to show the application of the concepts and method presented in this paper.     

温度和植物激素对提高南方红豆杉种子出苗率的研究

为提高珍稀药用植物南方红豆杉种子萌发活力和出苗率，采用暖冷变温层积法和不同植物激素对南方红豆杉种子进行了萌发试验研究。结果表明：经过变温层积处理，种胚长净增0．43mm，宽净增0．10mm。部分种子提早出苗，出苗率高达30％，综合出苗率（92％）比对照出苗率（80％）高出12个百分点；植物激素的作用使种子提前9个月萌发，萌发率和出苗率均高于对照；层积基质、播种基质的选择对其种子萌发也有重要作用。     

OPTIMAL ACTIVE POWER ADJUSTMEMT OF LARGE HYBRID AC/DC SYSTEMS AFTER OUTAGE CONTINGENCIES WITH THE APPLICATION IN RELIABILITY EVALUATION

An optimal active power adjustment model is deve in this paper for hybrid AC/DC systems after outage contingencies. The objective of the model is to minimize the rejection of load when some elements are out of service, with adjustment strategy approaching practical system operation. A large number of outage contingencies are simulated when the Monte-Carlo Method is emyloyed to evaluate the system reliability, requiring fast calculation of each simulation. The model and computer method proposed in this paper satisfy such a requirment because of the application of concentric relaxation, recursive branch constraint treatment in linear programming and a direct method for B-1 matrix modification. This paper is concerned with the simplified steady state conditions of the system based on DC load-flow, which implies the reliability indices calculated are the measures about static loss of load. The results for a 14-bus hybrid AC/DC system are given.     

兰州百合微繁的研究

以兰州百合的鳞茎增殖为基础，进行了离体微繁研究。鳞茎增殖的适宜激素组合为0.9 mg/L BA +0.1~0.2 mg/L NAA。培养基中总离子浓度和氮浓度过高或过低都会影响兰州百合增殖，3种基本培养基N6、MS、和1/2MS以N6增殖效果最好。适当提高糖浓度对鳞茎增殖有促进作用，在各处理中以蔗糖浓度为40 g/L增殖倍数高。兰州百合的适宜生根培养基为1/2MS+IBA0.1 mg/L，生根率达100%，生根苗移栽成活率达90%。     

胡萝卜,根芹,小麦的人工种子在无菌及有菌条件下的发芽成苗

用海藻酸钙凝胶包裹胡萝卜、根芹与小麦的体细胞胚制作的人工种子在无菌和有菌条件下皆可发芽成苗.     

60Co-γ射线对叶牡丹种子发芽率及生长的影响

用不同剂量60Coγ-射线辐射叶牡丹种子,观测对种子发芽率与幼苗生长的影响。结果表明:发芽率与辐射剂量呈负相关,根长、芽长与辐射剂量呈正相关。辐射可促进叶牡丹根、芽的生长,但抑制发芽率。70 Gy时芽长比对照组提高178.30%,90 Gy时根长比对照组提高194.48%,30 Gy最有利于种子生长。     

不同种源2年生毛红椿光合特性差异研究

采用Li-6400光合系统测定仪对分别来自官山自然保护区、马头山自然保护区和九连山自然保护区的3个2年生毛红椿种源,进行光合特性差异分析,结果表明:来自官山自然保护区的毛红椿种源,在高温强光下较之其它两个种源有较强的光合能力。毛红椿的净光合速率Pn日进程曲线呈"双峰"型,高峰出现在一天中的10:00和14:00左右,在天气晴朗情况下有较明显的光合"午休"现象。同时通过比较同一种源不同月份(8～10月)的光合特性得知,9月是毛红椿生长的一个高峰期。     

毛红椿天然林生长特性研究

分析毛红椿树高、胸径、材积生长特性,提出树高、胸径、材积生长规律和数量成熟年龄,为人工培育毛红椿大径材提供依据。     

小花棘豆对卡拉库尔羊瘤胃内环境的影响

试验将9只健康的卡拉库尔公羊分为3组,每组3只,分别为对照组、试验Ⅰ组和试验Ⅱ组,研究不同的小花棘豆添加量对卡拉库尔羊瘤胃内环境及微生物发酵参数的影响。结果表明,日粮中添加小花棘豆可降低卡拉库尔羊瘤胃液pH;随着小花棘豆添加量的增加,卡拉库尔羊瘤胃液氨氮含量升高,菌体蛋白含量下降;日粮中添加小花棘豆有促进瘤胃液总挥发性脂肪酸含量升高和乙酸/丙酸比降低的趋势。     

嵩明海菜花的核型分析

以我国云南省嵩明海菜花为试材,研究其体细胞染色体数目和核型(2n=2x=22=12m+8sm+2st)。结果表明:嵩明海菜花核型类型为"2B"型,与海菜花属的核型非常相近,这为进一步研究水鳖科海菜花属的系统演化提供了重要的细胞学资料,为海菜花的1个新变种提供细胞学依据。