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91.
T.Y. Abi-Salloum J. Yablon S. Tseng M. Salit M.S. Shahriar 《Journal of Modern Optics》2013,60(11):880-885
Recently, we have been investigating the development of a superluminal ring laser, where finely tuned anomalous dispersion leads to an enhancement in the sensitivity of the laser frequency to a change in the cavity length, by as much as six orders of magnitude, for applications such as hypersensitive rotation sensing and accelerometry, as well as for gravitational wave detection. For such a laser, as well as other lasers that are used for precision metrology, the effective dispersion – manifested in the manner in which the lasing frequency varies as a function of a change in the cavity length due to the index induced by the medium under saturated gain corresponding to steady-state lasing – is of utmost significance. In determining the effective dispersion, the role of inhomogeneous broadening (IB) must be taken into consideration carefully. In this work, we consider an inhomogeneously broadened gain medium in a single mode optical cavity, and study the effective dispersion experienced by the lasing field. It is well known that the steady state index for such a laser cannot be expressed analytically. Previous studies have employed approximate models to interpret the effective dispersion, in two limits: IB is much larger than homogeneous broadening (HB), and IB is insignificant compared to HB. Here, we use an iterative but quickly converging numerical code to determine the exact behavior of the effective dispersion under all conditions, and show that the results agree with the expected behavior in these two limits. This technique paves the way for taking into account the effective dispersion in any inhomogeneously broadened laser, including the superluminal laser, in determining accurately its sensitivity to change in cavity length, as well as it quantum noise limited linewidth. 相似文献
92.
Ozonation of complex industrial park wastewater: effects on the change of wastewater characteristics
Jen‐Mao Fanchiang Dyi‐Hwa Tseng Gia‐Luen Guo Hsi‐Jien Chen 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(7):1007-1014
BACKGROUND: Ozonation of complex industrial park wastewater was carried out in a semi‐batch reactor. The variation of wastewater characteristics was evaluated based on the analysis of 5‐day biochemical oxygen demand (BOD5) concentration, BOD5/chemical oxygen demand (COD) ratio, COD fractionation, and dissolved organic carbon (DOC) molecular size distribution before and after ozonation. RESULTS: The experimental results indicated that low efficiency of COD removal with increasing tendency of BOD5 concentration generally appeared after ozonation. Also, the BOD5/COD ratio increased from an initial of 0.27 to a maximum of 0.38. The COD fractionation tests revealed that most of the inert soluble COD was transformed to biodegradable soluble COD at 30 min of reaction time. Additionally, the DOC molecular size distribution tests showed that the fraction larger than 500 kDa was significantly decreased and the fraction smaller than 2 kDa was increased when the reaction time was prolonged to 240 min. CONCLUSION: This study verified that partial oxidation of the complex industrial park wastewater by ozonation could enhance wastewater biodegradability. The biodegradability enhancement was primarily because the inert soluble COD fraction was converted to the biodegradable soluble COD and the high molecular weight fraction of DOC was shifted toward the low molecular weight fraction. Copyright © 2009 Society of Chemical Industry 相似文献
93.
94.
High-performance, reliable, and robust products with a short development schedule are general design aims. FACE was developed to achieve these goals, including the organization of a design flow, a frequency-driven information analyzer, compiler techniques (code generator and instruction optimization), and a hierarchical object design library. This paper explores the design space of a retargetable compiler and a reconfigurable hardware, which combine both software and hardware reprogrammability. The environment, FACE, we have developed allows us to quickly move the functions between software and hardware in a state of flux. Finally, it generates the application specific integrated processor (ASIP) and a compiler for the new ASIP architecture. The case study is considered which demonstrates the efficiency in ASIP design of FACE. 相似文献
95.
King-Jet Tseng Shuyu Cao Jijiu Wang 《Industrial Electronics, IEEE Transactions on》2000,47(6):1228-1236
This paper presents an experimentally verified single-pulse-operation switched reluctance motor converter topology based on the basic buck-fronted topology and the modified C-dump topology. Using only (n+1) power switches, this topology is able to achieve full single-pulse operation, thereby reducing switching losses and acoustic noise. It also achieves a greater demagnetizing voltage compared to the basic buck-fronted topology, without having to increase the DC-source voltage. The converter is more robust as its dump capacitor stops being charged if the chopper switch fails. The principle of operation, modes of operation, transient simulation results, and experimental results are presented. 相似文献
96.
C.S. Huang Y.P. Tseng A.W. Leissa K.Y. Nieh 《International Journal of Mechanical Sciences》1998,40(11):1159
An exact solution for in-plane vibration of arches with variable curvature as well as cross section has been developed using the famous Frobenius method combined with the dynamic stiffness method. The effects of shear deformation and rotary inertia are taken into account. A convergent solution is always guaranteed without numerical difficulties. An important by-product of this series solution is that the first known dynamic stiffness matrix for an arch with variable curvature and variable cross section is also explicitly formulated. Some new numerical results are given for non-dimensional frequencies of parabolic arches with a certain type of variation of cross section along the arch that is often used in practical structures. Extensive and accurate (six significant figure ) non-dimensional frequency tables and graphic charts are presented for a series of parabolic arches showing the effects of rise to span length, slenderness ratio, and variation of cross section. 相似文献
97.
By using fiber gratings as pump reflectors with various reflectivities or N pieces of gain fibers with various lengths externally to linear cavity as self-equalizers, a parallel-type, pump-shared linear cavity laser array (LCLA) is proposed and numerically studied. The average output power is increased and the maximum power variation among channels is reduced from 7.2 to less than 0.1 dB when the reflectivity of each pump reflector or the length of each gain fiber is adjusted appropriately 相似文献
98.
Tzung-Pei Hong Shian-Shyong Tseng 《Knowledge and Data Engineering, IEEE Transactions on》1999,11(5):813-815
We have modified the original version space strategy in order to learn disjunctive concepts incrementally and without saving past training instances. The algorithm time complexity is also analyzed, and its correctness is proven 相似文献
99.
Tsung-Hsien Tsai Tzung-Hsun Tsai Wen-Huey Wu Jonathon Te-Peng Tseng Po-Jung Tsai 《Food chemistry》2010
Propionibacterium acnes play an important role in the pathogenesis of acne by inducing certain inflammatory mediators and comedogenesis. The objective of this study was to evaluate the antimicrobial and anti-inflammatory effects of herbal extracts against P. acnes. Among the ten tested herbs, methanolic extracts of rose (Rosa damascene), duzhong (Eucommia ulmoides Oliv.), and yerba mate (Ilex paraguariensis) were found to inhibit the growth of P. acnes with respective minimum inhibitory concentrations of 2, 0.5, and 1 mg/ml. In addition, duzhong and yerba mate extracts reduced the secretion of pro-inflammatory cytokines such as tumour necrosis factor-α, interleukin (IL)-8, and IL-1β by human monocytic THP-1 cells pretreated with heat-killed P. acnes at a concentration of 0.1 mg/ml. Our results suggested that duzhong and yerba mate extracts possess both antimicrobial and anti-inflammatory effects against P. acnes and can possibly be used as therapeutic agents for acne. 相似文献
100.
A miniaturized multilayer quasi-elliptic bandpass filter with aperture-coupled microstrip resonators
Chi-Feng Chen Ting-Yi Huang Chao-Hsiung Tseng Ruey-Beei Wu Tsung-Wen Chen 《Microwave Theory and Techniques》2005,53(9):2688-2692
A four-pole quasi-elliptic function bandpass filter for a compact low-temperature cofired ceramic is proposed in this paper. The filter is constructed by the open-loop resonators and the miniaturized hairpin resonators that can be coupled through the apertures on the common ground plane, and the 0/spl deg/ feed structure adds two extra transmission zeros to the filter response. It is shown that the filter occupies a very small size. As a result, the proposed structure of the filter occupies a very small circuit area and has a good out-of band rejection. 相似文献