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71.
本文用差示扫描量热法(DSC)测定了非线性光学晶体BBO、LBO和CLBO的恒压比热容,计算了在220~420K温度范围内每间隔10K的焓差值和熵差值.有关误差分析表明,该测试方法是有效的,并可用于其它晶体的恒压比热容的测量. 相似文献
72.
The authors study queueing, input and output processes in a queueing system with bulk service and state dependent service delay. The input flow of customers, modulated by a semi-Markov process, is served by a single server that takes batches of a certain fixed size if available or waits until the queue accumulates enough customers for service. In the latter case, the batch taken for service is of random size dependent on the state of the system, while service duration depends both on the state of the system and on the batch size taken. The authors establish a necessary and sufficient condition for equilibrium of the system and obtain the following results: Explicit formulas for steady state distribution of the queueing process, intensity of the input and output processes, and mean values of idle and busy periods. They employ theory of semi-regenerative processes and illustrate the results by a number of examples. In one of them an optimization problem is discussed. 相似文献
73.
本文报道LiB_3O_5(LBO)光参量振荡的运转.输出波长范围为:0.956~1.205μm和1.488~1.583μm(0.828~0.801μm).最高输出能量大于70mJ/pulse,效率为43%.文中还给出了双轴晶体LBO的相位匹配曲线和有效非线性系数的计算方法及结果. 相似文献
74.
In this paper we first obtain, in a unified way, closed-form analytic expressions in terms of roots of the so-called characteristic equation (c.e.), and then discuss the exact numerical solutions of steady-state distributions of (i) actual queueing time, (ii) virtual queueing time, (iii) actual idle time, and (iv) interdeparture time for the queueGI/R/1, whereR denotes the class of distributions whose Laplace-Stieltjes transforms (LSTs) are rational functions (ratios of a polynomial of degree at mostn to a polynomial of degreen). For the purpose of numerical discussions of idle- and interdeparture-time distributions, the interarrival-time distribution is also taken to belong to the classR. It is also shown that numerical computations of the idle-time distribution ofR/G/1 queues can be done even ifG is not taken asR. Throughout the discussions it is assumed that the queue discipline is first-come-first-served (FCFS). For the tail of the actual queueing-time distribution ofGI/R/1, approximations in terms of one or more roots of the c.e. are also discussed. If more than one root is used, they are taken in ascending order of magnitude. Numerical aspects have been tested for a variety of complex interarrival- and service-time distributions. The analysis is not restricted to generalized distributions with phases such as Coxian-n (C
n
), but also covers nonphase type distributions such as uniform (U) and deterministic (D). Some numerical results are also presented in the form of tables and figures. It is expected that the results obtained from the present study should prove to be useful not only to practitioners, but also to queueing theorists who would like to test the accuracies of inequalities, bounds or approximations. 相似文献
75.
Markov-modulated queueing systems are those in which the primary arrival and service mechanisms are influenced by changes of phase in a secondary Markov process. This influence may be external or internal, and may represent factors such as changes in environment or service interruptions. An important example of such a model arises in packet switching, where the calls generating packets are identified as customers being served at an infinite server system. In this paper we first survey a number of different models for Markov-modulated queueing systems. We then analyze a model in which the workload process and the secondary process together constitute a Markov compound Poisson process. We derive the properties of the waiting time, idle time and busy period, using techniques based on infinitesimal generators. This model was first investigated by G.J.K. Regterschot and J.H.A. de Smit using Wiener-Hopf techniques, their primary interest being the queue-length and waiting time. 相似文献
76.
Ryusuke Horiuchi Koichi Saiki Koji Adachi Kazuyoku Tei Shigeru Yamaguchi 《Optical Review》2008,15(3):136-139
A high-peak-power and high-repetition-rate fiber laser architecture is successfully demonstrated using a single-stage fiber
amplifier. Nonlinear optical effects in a fiber amplifier degrade the monochromaticity of amplified laser pulses. In general,
it is difficult for a non-monochromatic laser pulse to realize high-order harmonic generation with bulk nonlinear optical
crystals. To overcome this problem, a single-stage amplifier architecture and a gain fiber with a high cladding absorption
coefficient are employed. Furthermore, single-stage amplification enables the use of a multi-longitudinal mode electro-optically
(EO) Q-switched micro seed laser. This architecture can generate a peak power of 100 kW at 50 kHz and an average power of
10 W. A second-harmonic conversion efficiency of 51% is obtained using this architecture and a LiB3O5 (LBO) crystal. 相似文献
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80.
N. Pylneva V. Kosyakov A. Yurkin G. Bazarova V. Atuchin A. Kolesnikov E. Trukhanov C. Zilling 《Crystal Research and Technology》2001,36(12):1377-1384
The liquidus surface structure and field of LiB3O5 (LBO) primary crystallization have been revealed in Li2O‐B2O3 ‐MoO3 ternary system. The optimization of charge composition and growth conditions results in large volume optical quality LBO single crystals yielding. Crystallographic properties and real defect structure of grown LBO single crystals have been investigated by X‐ray powder diffraction method and X‐ray reflection topography. The volume of the crystals is partly free of any structural imperfections. 相似文献