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This map corresponds geometrically to restriction to the fixed point set of an action of a onedimensional torus on the flag variety of a semisimple group G.


It is known [M4] that K?orbits S and G?orbits S' on a complex flag manifold are in onetoone correspondence by the condition that S ∩ S' is nonempty and compact.


We construct a oneparameter family of flat connections ?κ on h with values in any finitedimensional gmodule V and simple poles on the root hyperplanes.


Aliasing error bounds are derived for one and twochannel sampling series analogous to the WhittakerKotel'nikovShannon series, and for the multiband sampling series, and a "derivative" extension of it, due to Dodson, Beaty, et al.


Aliasing in the onechannel case is shown to arise from a transformation with similarities to a projection.

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 In ordinary sampleddata control systems the system response to a step input can reach its equilibrium state only within n or more sampling intervals (n is the order of the controlled plant). In this paper multipleimpulses are used, instead of ordinary simple impulses, to speed up the system response. In such sampled data systems the system response to step input can reach its equilibrium state within less than n, even one, sampling intervals. Methods of design of such kind of sampleddata systems and... In ordinary sampleddata control systems the system response to a step input can reach its equilibrium state only within n or more sampling intervals (n is the order of the controlled plant). In this paper multipleimpulses are used, instead of ordinary simple impulses, to speed up the system response. In such sampled data systems the system response to step input can reach its equilibrium state within less than n, even one, sampling intervals. Methods of design of such kind of sampleddata systems and their components are discussed. In the last part of the paper methods of compensating sampled data systems with dead time elements is also considered.  在通常的脉冲控制系统中,当输入信号是阶跃函数时,系统的过渡过程至少在n个采样周期内才能完全结束(n是控制对象的阶数).文中考虑了采用宽度不等的多拍脉冲代替通常的单拍脉冲以加快系统的过渡过程.在采用多拍脉冲以后,系统的过渡过程可以在少于n个采样周期内,甚至在一个采样周期内完全结束.文中叙述了这种脉冲系统的综合方法,也讨论了系统中有关组成部分——脉冲组成器和校正装置——的构成方案及其参数的计算方法.最后并考虑了由于时滞引起的对系统动态特性有害影响的补偿问题.文中举有例题,对文中各节内容作必要的说明.  In this paper the logical structure of contactless telemechanical system for distributed objects is discussed. A simple method of variable system structure for transmitting and receiving telemechanical information is adopted. The idea is that the information occurred in every controlled point (station) and the information of some of those objects,which frequently change their states, are transmitted continually and cyclically, while for other objects their information is transmitted only after any change in... In this paper the logical structure of contactless telemechanical system for distributed objects is discussed. A simple method of variable system structure for transmitting and receiving telemechanical information is adopted. The idea is that the information occurred in every controlled point (station) and the information of some of those objects,which frequently change their states, are transmitted continually and cyclically, while for other objects their information is transmitted only after any change in their states. Thus,the speed of operation will be increased, and also the error probability of system synchronization will be decreased. For the realization of the variable logical system structure, several blocks are used repetitively. For example, two commutators and one simple logical unit are used to construct a simple automatic sequential encoder, and at the same time, the two commutators are used also to operate as a matrix commutator for receiving telesignalling information etc. Therefore the system is comparatively simplified and attains a higher degree of "minimization".  本文研究了无触点集中分散目标远动系统的逻辑结构.文中提出了采用简单的系统变结构来发送和接收信息的逻辑结构方式.对被控制点及一部分比较重要或变化比较频繁的被控制目标的信息,保留了循环传送,而对大部分变化比较慢的被控制目标则采用目标有变化时才传送信号的方式,这样就提高了系统的平均动作速度,同时也减小系统的失步概率.文中采用环节的复合利用及简化的逻辑单元线路来实现这种系统的逻辑结构.例如用两个分配器和一个简单的逻辑单元“和”线路组成了很简化的选点自动程序编码器,同时这两个分配器又复合利用兼组成目标信号接收矩阵式分配器等,因而可以使得这种系统同时又具有较高的极简化度.  Emission and absorption band spectra of sulphur dioxide were studied in the region between 2600 to 2000 A.U. A new system of emission bands (about 150 bands) was found. When these bands were compared with the absorption bands and Mr. Lotmar's fluorescent bands, coincidences were found which amount to 40% and 50% of the total number of absorption and fluorescent bands respectively. These agreements and the very different structure as compared with the SO bands recorded on the same plate made it very probable... Emission and absorption band spectra of sulphur dioxide were studied in the region between 2600 to 2000 A.U. A new system of emission bands (about 150 bands) was found. When these bands were compared with the absorption bands and Mr. Lotmar's fluorescent bands, coincidences were found which amount to 40% and 50% of the total number of absorption and fluorescent bands respectively. These agreements and the very different structure as compared with the SO bands recorded on the same plate made it very probable that SO2, is the emitter of these emission bands. Evidences were also found that these emission bands arc not the known bands of O2, Oa+ and S2 in the same region. As a further support a vibrational level scheme was worked out, using the three fundamental frequencies of the normal SO2, molecule (1150, 525, and 1360 cm1) in the lower state and 750 and 350 cm1 (possible also 1110 cm1) as the frequencies in the upper state. This scheme accounts for 1Q% of the absorption bands, 70% of the emission bands and a small fraction of the fluorescent bands. While the scheme may not be the final due to the complexity of the vibrational formula, one feels fair, as far as the present evidence goes, to conclude that the emission bands observed are actually emitted by the SO2, molecules and that they can be fitted by a vibrational level scheme based on the three known fundamental frequencies of the normal state.  此文目的在报告二氧化硫气体分子之吸收光谱及发射光谱(emission speetrun)之研究光谱区域约在2000A与2600A间有一新组发射光带(band)发现。数约百五十在吸收光带中有百分之四十之光带与此发射光带附合。在Lotmar先生之弗光光谱(fluorescent speetrum)中,有百分之五十之光带与此发射光带附合并此所得之发射光带之结构与SO之光带显有区别,令人设信此发射光带为SO_2分子所发者。在另一方面,找到证据,所得之发射光带亦非0_2,O_2~+及S_2诸分子之光谱为求更进一步之证实,试以SO_2之三基本振动数(fundamental frequency)1150,525及1360cm~(1)为能力阶梯之差而作一常态(normal state)下之能力阶梯。再用750,350cm~(1)(或1110亦用)为分子在激态(excited state)时之振动数,而作一激态下之能力阶梯所得之能力图(energydiagram)可说明吸收光带之70%,发射光带之70%及弗光光带之一小部份,此能力图并不完全,故不能望其为最终者。以三原子分子情形复杂,完全正确之分析,尚有待焉。之 能 力唯协... 此文目的在报告二氧化硫气体分子之吸收光谱及发射光谱(emission speetrun)之研究光谱区域约在2000A与2600A间有一新组发射光带(band)发现。数约百五十在吸收光带中有百分之四十之光带与此发射光带附合。在Lotmar先生之弗光光谱(fluorescent speetrum)中,有百分之五十之光带与此发射光带附合并此所得之发射光带之结构与SO之光带显有区别,令人设信此发射光带为SO_2分子所发者。在另一方面,找到证据,所得之发射光带亦非0_2,O_2~+及S_2诸分子之光谱为求更进一步之证实,试以SO_2之三基本振动数(fundamental frequency)1150,525及1360cm~(1)为能力阶梯之差而作一常态(normal state)下之能力阶梯。再用750,350cm~(1)(或1110亦用)为分子在激态(excited state)时之振动数,而作一激态下之能力阶梯所得之能力图(energydiagram)可说明吸收光带之70%,发射光带之70%及弗光光带之一小部份,此能力图并不完全,故不能望其为最终者。以三原子分子情形复杂,完全正确之分析,尚有待焉。之 能 力唯协所得之能 力 圆 山。。。,。w山。…。。。。\可。Z5t 叫 吸收 几 卅之70九传 时 光排 上 7,％及 比 儿 儿 卅上 一 个 部 份 此 能 力 闲 伙 不 正 全;故个能 望IC iX侦相 许 nt原一户 外 广似形 应 输,完全 正雕之分 析。尚有   << 更多相关文摘 



