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11.
声学多普勒流速剖面仪(ADCP)测流技术是目前海流测量中最先进的技术之一,在海流测量中应用越来越广泛.但在高干扰条件下,由于其本身测量原理所致,测量结果往往会夹杂一些干扰信号,造成测量结果与真实结果有一定大的误差.文中介绍一种利用卡尔曼滤波技术,使用Percent Good4作为参数,对ADCP海流测量数据的实时滤波处理方法.实践证明,滤波的效果比较令人满意.  相似文献   
12.
Fabrication of 1.55μm Si-Based Resonant Cavity Enhanced Photodetectors   总被引:1,自引:1,他引:0  
A novel bonding method using silicate gel as bonding medium is developed.High reflective SiO2/Si mirrors deposited on silicon substrates by e-beam deposition are bonded to the active layers at a low temperature of 350℃ without any special treatment on bonding surfaces.The reflectivities of the mirrors can be as high as 99.9%.A Si.based narrow band response InGaAs photodetector is successfully fabricated,with a quantum efficiency of 22.6% at the peak wavelength of 1.54μm,and a full width at half maximum of about 27nm.This method has a great potential for industry processes.  相似文献   
13.
1.IntroductionAsanewkindofrareearthmolybdenumcathodematerial,MoY2O3isexpectedtosubstituteradioactiveWThO2cathodematerialsinthefuture.Mo4wt%Y2O3allows,relativetoMoLa2O3〔12〕(whichhasbeenwidelystudiedsince1970sinordertosubstituteWThO2cathodemater…  相似文献   
14.
不饱和聚酯光敏预聚物的合成   总被引:8,自引:0,他引:8  
采用熔融缩聚法制备了光敏不饱和聚酯树脂(UPR),对其进行了红外表征,研究了酸值与反应时间的关系及酸醇比等对UPR玻璃化温度(Tg)的影响,讨论了第一阶段反应时间对光敏不饱和聚酯合成反应的影响。得到的优化工艺条件为:酸/醇(摩尔比)=2.0:1.95,己二酸含量为10%(对酸的摩尔分数),制得的树脂Tg为54℃,可满足紫外光固化粉末涂料的要求。  相似文献   
15.
Jasmonic acid (JA) is an important hormone that functions in plant defense. cam1 and wrky53 mutants were more resistant to Spodoptera littoralis than in the wild-type (WT) Arabidopsis group. In addition, JA concentration in cam1 and wrky53 mutants was higher compared with the WT group. To explore how these two proteins affect the resistance of Arabidopsis plants, we used a yeast two-hybrid assay, firefly luciferase complementation imaging assay and in vitro pull-down assay confirming that calmodulin 1 (CAM1) interacted with WRKY53. However, these two proteins separate when calcium concentration increases in Arabidopsis leaf cells. Then, electrophoretic mobility shift assay and luciferase activation assay were used to verify that WRKY53 could bind to lipoxygenases 3 (LOX3) and lipoxygenases 4 (LOX4) gene promoters and negatively regulate gene expression. This study reveals that CAM1 and WRKY53 negatively regulate plant resistance to herbivory by regulating the JA biosynthesis pathway via the dissociation of CAM1-WRKY53, then the released WRKY53 binds to the LOXs promoters to negatively regulate LOXs gene expression. This study reveals WRKY53′s mechanism in insect resistance, a new light on the function of WRKY53.  相似文献   
16.
Gonadotropin-inhibitory hormone (GnIH) is a reproductive inhibitor and an endogenous orexigenic neuropeptide that may be involved in energy homeostasis and reproduction. However, whether GnIH is a molecular signal link of metabolism and the reproductive system, and thus, regulates reproductive activity as a function of the energy state, is still unknown. In the present study, we investigated the involvement of GnIH in glycolipid metabolism and reproduction in vivo, and in the coupling between these two processes in the testis level. Our results showed that chronic intraperitoneal injection of GnIH into male mice not only increased food intake and altered meal microstructure but also significantly elevated body mass due to the increased mass of liver and epididymal white adipose tissue (eWAT), despite the loss of testicular weight. Furthermore, chronic intraperitoneal administration of GnIH to male mice resulted in obesity-related glycolipid metabolic derangements, showing hyperlipidemia, hyperglycemia, glucose intolerance, and insulin resistance through changes in the expression of glucose and lipid metabolism-related genes in the pancreas and eWAT, respectively. Interestingly, the expression of GnIH and GPR147 was markedly increased in the testis of mice under conditions of energy imbalance, such as fasting, acute hypoglycemia, and hyperglycemia. In addition, chronic GnIH injection markedly inhibited glucose and lipid metabolism of mice testis while significantly decreasing testosterone synthesis and sperm quality, inducing hypogonadism. These observations indicated that orexigenic GnIH triggers hyperphagia-induced obesity-related metabolic derangements and hypogonadism in male mice, suggesting that GnIH is an emerging candidate for coupling metabolism and fertility by involvement in obesity and metabolic disorder-induced reproductive dysfunction of the testes.  相似文献   
17.
The mode of mobile computing originated from distributed computing and it has the un-idempotent operation property, therefore the deadlock detection algorithm designed for mobile computing systems will face challenges with regard to correctness and high efficiency. This paper attempts a fundamental study of deadlock detection for the AND model of mobile computing systems. First, the existing deadlock detection algorithms for distributed systems are classified into the resource node dependent ( RD ) and the resource node independent (RI) categories, and their corresponding weaknesses are discussed. Afterwards a new RI algorithm based on the AND model of mobile computing system is presented. The novelties of our algorithm are that: 1 ) the blocked nodes inform their predecessors and successors simultaneously; 2) the detection messages (agents) hold the predecessors information of their originator; 3 ) no agent is stored midway. Additionally, the quit-inform scheme is introduced to treat the excessive victim quitting problem raised by the overlapped cycles. By these methods the proposed algorithm can detect a cycle of size n within n - 2 steps and with ( n^2- n - 2 )/2 agents. The performance of our algorithm is compared with the most competitive RD and RI algorithms for distributed systems on a mobile agent simulation platform. Experiment results point out that our algorithm outperforms the two algorithms under the vast majority of resource configurations and concurrent workloads. The correctness of the proposed algorithm is formally proven by the invariant verification technique.  相似文献   
18.
目前,山东纺织工学院正在教育改革与开放的指引下迅速发展。学院科研新立项28个;已获科研经费104.6万元;在美国匹兹堡国际博览会上,我院教师获银牌奖;许多重大科研项目转化为生产力;获国家自然科学基金项目三项;教师队伍结构迅速优化以及校办产业的迅猛发展都为学院发展展示了良好的前景。抓住机遇,深化改革和创造性工作是高校今后工作的关键。文章用现代管理学的观点从不同角度论述了高校发展的关键问题,立题新颖,颇有新意。  相似文献   
19.
Achieving a thorough understanding of how primary sedimentary granularity drives considerable het-erogeneity in internal reservoir attributes of terrigenous fin...  相似文献   
20.
针对电力通信系统运行特点,着重对电力系统接地故障引起的地电位升高及其对通信设备的影响进行了分析,提出了相应的保护措施,并介绍了两种保护装置。  相似文献   
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