6 resultados para System Management Development

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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A multi-channel gated integrator and PXI based data acquisition system have been developed for nuclear detector arrays with hundreds of detector units. The multi-channel gated integrator can be controlled by a programmable Cl controller. The PXI-DAQ system consists of NI PXI-1033 chassis with several PXI-DAQ cards. The system software has a user-friendly GUI which is written in C language using LabWindows/CVI under Windows XP operating system. The performance of the PXI-DAQ system is very reliable and capable of handling event rate up to 40 kHz. (C) 2010 Elsevier B.V. All rights reserved.

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From the organizational behavior point, this study initially explored how factors of educational changes influenced on teachers. This study adapted the questionnaire made up by Consortium for Cross-Culture Research in Education (CCCRE), by cooperating with other countries, interviewed 513 teachers in nine countries. The main results are as follows: 1. Factors of educational changes include: domain, origin, objective, teachers' role, and timetable. Comparative results show: More similarities than differences tend to be presented in five factors. The detail results are: in domain, it mainly involves teaching change and learning outcomes change; in origin, the educational change most teachers participated was initialed by government; in role, teachers more act as the implementer; in timetable, gradual development is the chief characteristic. 2. The domain of change, origin and teachers' role has a significant impact on the quality of worklife of teachers, but timetable of change has not. The further study about the influence of educational origin on the quality of worklife of teachers shows: Changes of teachers' time -using, professional development were significantly impacted by the origin of education, and there is a significant difference in the change of time-using among nine countries. 3. Change on students, change on teachers' relationship are two important factors to impact the teachers' evaluation about educational change. But the teachers' evaluation, teaching age and the change on relationship are valid factors to predicate teachers participate in next educational change. 4. Compared with the educational change of other eight countries, the change in school system management and the change in learning outcomes are more carried on in China. There is no significance about other factors between China and overall nine countries. In China, the educational change has a more positive impact on teachers' time-using and professional development, but professional development is also a important factor to impact teachers' evaluation on change; however there is a negative relationship between the Chinese teachers' evaluation and the teachers' participation in next change.

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本文以正常性玉米种子‘农大108’(Zea Mays L. ‘Nongda 108’) 种胚为实验材料,研究了玉米种子发育过程中脱水耐性的变化规律,细胞匀浆以及线粒体水平上活性氧清除酶活性与种子脱水耐性/敏感性的关系,以及线粒体结构和功能完整性在发育过程中不同阶段对脱水的应答,以期在亚细胞分区水平上,针对活性氧产生的源头位点 (线粒体) 探明种子细胞脱水耐性/敏感性与抗氧化系统运转的关系。结果表明: 玉米种子在发育过程中先获得萌发能力后获得脱水耐性,并且脱水耐性的获得是一个渐进的过程。人工授粉后26天 (Days after pollination, DAP) 之前的种胚不具有脱水耐性,26 DAP时开始获得脱水耐性,到34 DAP后种胚完全获得脱水耐性。 在发育过程中,种胚线粒体的呼吸速率逐渐降低,并且对脱水的敏感性也逐渐下降。脱水会降低脱水敏感性种胚线粒体的结构完整性;脱水同时会降低线粒体功能的完整性,包括线粒体能量产生的速率和效率,以及三羧酸循环关键酶的活性。但当种胚获得脱水耐性后,脱水将不再影响种胚线粒体结构和功能的完整性。 玉米种胚发育过程中脱水耐性的变化与细胞中的抗氧化系统有关。在细胞匀浆水平上,脱水过程中脂质过氧化产物的积累与细胞脱水耐性的关系不明显;但是在线粒体水平上脱水会明显导致脱水敏感性种胚线粒体膜质过氧化程度的升高。脱水导致脱水敏感种胚细胞中几个重要的抗氧化酶活性的下降,但是与细胞匀浆水平相比,在线粒体水平上抗氧化酶系统对脱水更加敏感。 总之,发育早期玉米胚对脱水之所以敏感有两方面的原因,一方面是发育早期线粒体具有较高的代谢速率因而产生过多的活性氧,另一方面是由于脱水导致各抗氧化酶活性的显著降低,失去了抗氧化保护功能。而在发育晚期,早期本来很活跃的许多代谢随之关闭,呼吸速率降到很低,因而产生的活性氧减少,同时由于抗氧化系统对脱水的耐受性,所以脱水不会对线粒体的结构和功能造成伤害。与细胞匀浆水平相比,线粒体水平上抗氧化系统的运转与种胚在发育过程中脱水耐性的获得的关系更加密切。

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genetics, such as: population size, reproduction, mating system, growth, development,genetic structure and systematics status; The main results are presented below: The seasonal variation of the operational sexual ratio of this animal was found in the field and the ration always bias the female in the breeding season. Aiming at this character and considering the distance of time and space of both sexual habitat in breeding season, we census female population first by toe-clipping mark-recapture method, then estimated the population size with the definitive sexual ratio. Up to now, this species was found only at the Beilun district of the Ningbo City. The population size of the Ruiyan Temple Forest Park approximates to 369. The status of this population is extremely endangered, so besides protecting this population at the original locality, we also suggested to breed the salamander in fenced locality and to hatch embryos artificially, and send metamorphosed juveniles back to nature. We can transfer some individuals to other similar habitats or breed them under artificial conditions for saving this species from extinction. The early developmental stage of the Chinhai salamander is the same as its relative species, E. andersoni. Their balanceres are poorly developed and disappear very early. Temperature and moisture significantly influence the embryonic development of the Chinhai salamander. The embryonic stage is approx. 29 days under room temperature. The hatchling grows in a logarithmic curve. The larvae stage in water is approx. 58- 88 days. Many factors influence the nomal development, including two aspects of internal and external. Due to these factors, the effective protected measures were presented in detail. The breeding migration of E. chinhaiensis takes place at late March~late April every year. This salamander's hatching rate is high, but the rate of hatchling migrating into water is low. The average effectiveness of all the nest sites is 36.7%. The maternal self-conservation was contrary to the reproductive success of the egg-laying strategy. In the strategy of egg-laying behavior, the first factor selected by the female was its self-conservation, the second is embryonic survival rate, and the last is rate of hatchling survival rate. The oviposition selection is significant for the survival of the larvae. Based on the analysis of the evolutionary process of reproductive behaviors nad egg-laying site selections of all genera of the family Salamandridae, we deduced that perhaps Echinotriton is a transitional type in the evolutionary process from water to land. Due to its location in the adaptive stage in the terrestrial evolution, Echinotriton chinhaiensis's terrestrial nest may be one of important reason that causes this species to be endangered. The genetic deversity analysis shows that although the population size of the Chinhai salamander is quite small compared to other Chinese salamandrid species, the genetic diversity of this population is not reduce remarkably. We explain this phenomena with the polygamy mating system of this species. The result of 4 families' parenthood determinations shows that the parenhood determination can be taken without any paternal information. The "children" of every female include rich genetic information from at least two "fathers". It implies that female Chinhai salamander mates more than once with different males in a breeding season. The molecular evidence, the behavioral observation evidences and the sperm evidence in the female cloaca proved that this species has a polygamy mating system. The kin recognition in the mating of adult salamander was first discussed. The taxonomic status and phylogenetic relationships of 12 species representing 6 genera in the family Salamandridae were studied using DNA fingerprinting. The results showed that the DNA fingerprinting. The results showed that the DNA fingerprinting patterns demonstrated rich genetic diversity and species diversity, and also revealed the taxonomic status and phylogenetic relationshipes of higher taxa to a certain extent. The results are highly consistent with those obtained from the studies based on the morphology, ecology, cytology and molecular biology. The compreshensive analysis indicate that Tylototrition hainanensis and T. wenxianensis should be valid species; Echinotriton should be a valid genus;Tylotortriton is a natural cluster; Tylotortriton asperrimus should be put in Tylototrition rather than in Echinotriton, Hypselotriton and Allomestriton are synonyms of Cynops and Paramesotriton, respectively. There are three main groups in Chinese salamandride: Cynops, Paramesotriton and Pachytrition from the first group, the species of the Tylototriton from the second, and E. chinhaiensis composes the third.

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论文的结构分为空间望远镜系统的设计和硅(锂)探测器研制两个部分。第一部分主要介绍了空间望远镜系统的设计,该空间望远镜系统能鉴别Z≤26、M≤56范围内的空间带电粒子,该系统的设计在国内是首例,它将使我国空间高能带电粒子的鉴别和测量上一个新的台阶;第二个部分主要介绍适合于探测空间粒子的硅(锂)探测器的研制及其性能的测试过程。该探测器的研制成功为空间高能带电粒子的探测提供了必要的准备。 我们已经提供给空间科学与应用研究中心二十多块硅(锂)探测器。我们用ThC'-C源和137Cs源对硅(锂)探测器进行了测试,我们在120V时便可得到137Cs电子谱;我们在250V常温常压得到α粒子谱,其能量分辨可好于37Kev,长期加压测试时硅(锂)探测器的反向电流变化稳定,在持续20天加压250V时,其中直径为12mm的硅(锂)探测器的电流变化可达1.10±0.50微安,信噪比可达420倍。

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本文依托于中科院沈阳自动化研究所自动化装备研究室的项目——PASSIM卷接机组改造。PASSIM卷接机组是从英国MOLINS公司引进的设备,限于当时的硬件设计技术、芯片封装技术和通信技术,导致系统控制体积大,系统内部之间的连接也很复杂,同时旧的检测标准也不符合现在的要求。在消化吸收了国外设计思想的基础上,开发出了新型的烟支质量检测控制系统。在新的检测控制系统中采用了TI公司的DSP处理器,TMS320F2812完成系统中的数据采样、A/D转换和数据处理等功能,由于DSP处理器的A/D 采样精度高,运算速度快,满足了系统在速度和精度上的要求;同时,系统选用CYGNAL公司的单片机8051F020与上位机进行RS-485数据通讯,DSP与单片机之间采用双口RAM来共享数据。系统很好的完成了数据采集处理和数据交换的功能,对烟支质量做到了检测准确,剔除实时,取得了良好的使用效果。 本文首先对卷烟机的构成和控制系统作了简单的分析和介绍,剖析了烟支质量检测的原理,包括重量、稀释度和空头信号的产生,采集和处理。接着详细阐述了系统的具体方案设计,结合卷烟机工艺要求,按检测信号的分布将系统分为三个检测子站,对子站的设计进行了详细的分析。设计分为硬件和软件部分,硬件部分包括芯片的选择和接口电路的实现,软件则主要用来实现对重量、稀释度和空头信号的处理分析,及时剔除不合格烟支。最后介绍了系统在现场对传感器的校准和参数调整过程,并对运行结果进行了分析,实践证明系统是高效可靠的,满足了检测和控制的要求。