基于改进GM(1,1)模型的黄金价格预测

随着信息系统的发展,对黄金价格建立了基于新陈代谢理论的无偏灰色GM(1,1)预测模型。该模型是对GM(1,1)模型的改进,在不断补充新信息的同时,及时地去掉老信息,避免随着信息的增加,建模运算量不断增大的困难。实证结果表明,该模型预测精度优于GM(1,1)模型及无偏GM(1,1)模型的预测精度。     

基于灰色系统理论的加工番茄产量预测模型研究

[目的]研究基于灰色系统理论的加工番茄产量预测模型.[方法]运用灰色系统理论研究了加工番茄产量变化趋势,建立了加工番茄产量预测的GM(1,1)灰模型,并以2001～2009年新疆加工番茄产量为例,进行了实例分析.[结果]该模型有较高的预测精度和较强的泛化能力,对近期加工番茄产量的预测是可靠的.[结论]为新疆地区番茄产业的宏观调控、番茄加工及储藏等方面提供了参考.     

应用灰色系统理论预测全国钢产量

本文简要介绍了灰色系统的概念,灰色系统中GM(1,1)预测模型及其推导过程,并应用该模型预测了1988年全国钢产量。最后通过几种方法预测结果的比较,证明该模型是一个精确度较高的预测模型。     

灰色理论在矿山安全事故预测中的应用

以我国非煤矿山事故统计数据为依据,应用灰色系统理论建立事故死亡人数的GM(1,1)灰色预测模型,经误差和关联度检验表明,预测精度良好。用该模型对我国非煤矿山的安全状况进行预测,得出死亡人数的变化曲线,表明我国非煤矿山事故死亡人数呈逐年下降趋势。     

灰色预测线性规划在多金属矿产能优化配置中的应用

利用灰色预测线性规划模型对多金属矿山的产能进行优化配置.经过灰色预测模型对各定位系数进行预测,将灰色线性规划问题转化为一般的线性规划问题,对其进行求解.结果表明,定位系数GM(1,1)误差检验合格,预测的多金属矿山经产能优化后可以实现生产资料的合理配置和利润的最大化.     

基于模糊灰色预测模型的油菜产量预测

把模糊数学和灰数学有机的结合为模糊灰色预测FGM(1,1)模型,并应用到油莱产量的预测上,实例分析发现FGM(1,1)模型预测我国油菜产量具有较高的预测精度.     

基于灰色系统理论的矿区重金属污染预测分析

矿区重金属污染系统具有灰色系统的特征,因此可以采用灰色模型对重金属污染进行预测。运用灰色模型GM(1,1)对矿区Cu污染因子发展变化进行动态关联分析,作出了预测并对预测结果进行了分析,结果证明GM(1,1)模型是一种行之有效的预测金属污染的模型。     

基于GM(1,1)模型对房地产投资额的预测研究——来自四川省成都市的经验证据

针对房地产开发投资额样本数据少、受各种因素影响具有不确定性的特点,运用灰色理论中应用最为广泛的GM(1,1)模型,以2004年以来成都房地产开发投资额的年统计数据为样本,对成都2009年的房地产开发投资额进行拟合.实证分析过程中通过弱化缓冲序列算子的作用,调整了样本数据的增长速度,实证结果表明GM(1,1)模型在房地产开发投资额预测方面精度较好,能够用该GM(1,1)模型对成都未来的房地产开发投资额进行预测分析,为政府、投资者、消费者的决策提供参考意见.     

锰产品产量的灰色预测

锰业系统具有信息不完全、不确知的特点,故选用灰色理论来对锰产品进行建模和预测.GM(1.1)模型的实质是对原始数据作一次累加生成,然后以指数曲线作为逼近模型.用后验差检验方法对横型进行检验,满足一级精度。利用GM(1,1)模型,对湖南及全国锰产品产量长远规划进行了预测.到2000年,我国锰矿石产量完全可以满足我国钢铁工业的需求,而锰系铁合金将供大于求,电解金属锰发展速度较快,应提高质量,发展高新产品。     

硫酸盐环境下污染混凝土抗压强度灰色预测模型

为了分析污染混凝土抗硫酸铵腐蚀的力学性能,本文运用灰色理论建立单变量的一阶灰色预测模型GM(1,N),并用已有原始试验数据与模型预测的数据进行比较。研究得到利用GM(1,1)模型得到的预测数据与实际数据比较吻合,且平均相对误差较小,在数据较少时该模型可以较为有效的预测受硫酸盐腐蚀的污染混凝土的抗压强度。     

Changes in the ultra-fine structure of capillaries of the embryonic brain in the presence of schizophrenia in the mother

The report is concerned with a study of fine structures of brain capillaries in 9 embryos received during medical abortions from schizophrenic mothers. The authors established some traits in the ultrastructure of endothelial cells in most of the studied cases--an increase of the surface of endothelial cells at the expense of a tortuosity of their plasmatic membranes and a formation of growths, vacuolization of the cytoplasma. There were also some changes in the structure of basal membranes. In 2 cases there were also peculiar pathological changes in the vascular endothelium: granules of an unknown nature in the endothelial cells and a focal lysis of the plasmatic membranes of endothelial cells.     

不同除草剂在直播冬油菜田的除草效果研究

[目的]验证不同除草剂的除草效果,为直播冬油菜田的杂草防除提供借鉴.[方法]使用不同剂量25%胺苯磺隆可湿性粉剂和10.8%高效氟吡甲禾灵乳油在直播冬油菜田间进行单用和混用除草试验.[结果] 25%胺苯磺隆可湿性粉剂在冬油菜4～5叶期使用可以有效防除田间的阔叶杂草;25% 胺苯磺隆可湿性粉剂18.0～22.5 g/hm<'2>+400 ml/hm<'2>的10.8%高效氟吡甲采灵乳油可以有效防除油菜田间的阔叶和禾本科杂草,总防效达90%以上,且可以比人工除草节省成本1 100元、hm<'2>.[结论] 25%胺苯磺隆与10.8%高效氟吡甲未灵乳油混用可以更好地防除冬油菜田间杂草.     

Simulation of the solidification of the melt in the Vanyukov furnace in the case of emergency stoppage

A mathematical model of the Vanyukov furnace, which makes it possible to predict the behavior of an object in the emergency operational mode (upon the disconnection of the oxygen supply) and develop an effective system of additional heating which damps the consequences of the emergency mode and lowers the costs for the renovation of the furnace operation, is created. It is shown how solidification upon cooling the furnace with time is simulated using the enthalpy and porosity method. The mathematical model is adopted for existing production conditions, which are weakly defined. The energy characteristics of the mode for the solidifying furnace bath, which ensures its holding for a long time in the ready state to rapid firing, are found. Thus, the problem of excessively expensive furnace firing after prolonged production stoppage is solved in the conjugated statement with a calculation of the heating system of the overbath space.     

Variations in the relationship of the major vessels of the left coronary groove in the dog

The anatomic relationship of the 2 major vessels of the left coronary groove was studied in 140 dogs. Five basic patterns of disposition were observed: 1) circumflex artery superficial from its origin to the caudodorsal cardiac margin, coronary vein deep and not visible (22%); 2) coronary vein superficial from the ventral interventricular septum to the caudodorsal cardiac margin, circumflex artery deep and not visible (15%); 3) circumflex artery and coronary vein both superficial and running parallel with each other along the groove (8%); 4) coronary vein crossing circumflex artery at some point along the groove (44%); and 5) circumflex artery crossing coronary vein at some point along the groove (11%). These variations were found to influence certain experimental modifications of the left circumflex blood flow in the dog.     

Errors in the surgery of the testicle in children

The study was made of labyrinthine changes induced by lasix dehydration. Changes indicative of Meniere's disease were identified at comparison of the findings obtained by audiological lasix test, caloric optokinetic reactions. Four types of the nystagmic response in the bithermal lasix-test were determined. These reactions are helpful for more precise staging of the disease.     

Regional differences in the distribution of catalase in the epithelium of the ocular lens

The objectives of this study were to develop a system to calculate the economic consequences of accidents and to account for the economic consequences of all accidents during 1 year in a district. A total population injury survey was done in an area with a population of over 41,000. All accidents (N = 4926) occurring within a 12-month period and requiring medical care were noted. The costs (calculated at 1991 prices) to the health care service (outpatient care, including primary health care and hospital care) were SEK 23.7 million (US $3.59 million), to trade and industry SEK 79.7 million (US $12.08 million), and for health insurance SEK 9.1 million (US $1.38 million). The cost for society of uninsured people is not possible to estimate using loss of production. However, the time lost from "normal activities" was registered. If this time is valued at the same price as working hours, a welfare cost of SEK 43.1 million (US $6.53 million) should be added. In a forthcoming paper, an assessment of the cost-effectiveness of interventions against accidents will be published.     

A change in the state of neurons of the arcuate region of the hypothalamus in different stages of the sexual cycle in rats

With the help of microionophoretic stimulation of individual neurons of the arcuate region of the hypothalamus and the registration of its activity, changes in the sensitivity to dopamine during several stages of the sexual cycle of rats was studied. It was shown that in the 1st half of the day of proestrus the majority of neurons of the arcuate region, in correspondance to the increase in the level of estrogens in the blood plasma during this phase of the cycle, were activated by microionophoretic injections of dopamine. In the 2nd half of the day of proestrus, when the level of estrogens is minimal, and in the Diestrous-2 stage, it was observed that among registered neurons, those activated by dopamine were the most inhibited.     

The role of the forestomachs in the adaptation of the alimentary function in ruminants

Dietary character of ruminants in the north is principally different between "nonselective" (cattle, sheep) and "selective" (reindeer, moose) species. Due to the developed polyfunctioning, forestomach in ruminants, primarily rumen and reticulum, are involved in the homeostasis formation in enteral and interior mediums, nutrients deposition and recirculation. That provides efficiency in utilization of deficient in nutrients forage and body reserves of wild ruminants during the winter. The original functional organization of absorption processes and nutrients recirculation across the multilayer epithelium of forestomach also promotes realization of the two levels metabolism during the year and adaptation of wild ruminants to season dynamics of nutrition.     

Role of the subthalamo-nigral input in the control of amygdala-kindled seizures in the rat

The substantia nigra pars reticulata (SNpr) is a critical site for the control of epileptic seizures. Potentiation of the inhibitory GABAergic input from the striatum to the SNpr suppresses primary or secondary generalized seizures in the rat. The purpose of this study was to examine the possible involvement of the excitatory glutamatergic input from the subthalamic nucleus to the SNpr in the control of both the electroencephalographic and the motor components of amygdala-kindled seizures in the rat. Microinjections of either an N-methyl-D-aspartate (NMDA) antagonist in the substantia nigra or a GABAA agonist in the subthalamic nucleus, significantly reduced motor seizures but did not modified the afterdischarges. These results provide evidence for the involvement of the subthalamo-nigral projection in the modulation and the propagation of the motor components of amygdala-kindled seizures.