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41.
Recently, progress has been made in the Generalized Multi-Protocol Label Switching (GMPLS) and Automatic Switched Optical
Networks (ASON) standardizations. These technologies realize construction of large-scaled optical networks, interconnections
among single-domain Wavelength Division Multiplexing (WDM) networks, and direct communication over multi-domain WDM networks.
Meanwhile, it is known that the topology of the Internet exhibits the power-law attribute. Since the topology of the Internet,
which is constructed by interconnecting ASs, exhibits the power-law, there is a possibility that large-scale WDM networks,
which are constructed by interconnecting WDM networks, will also exhibit the power-law attribute. One of the structural properties
of a topology that adheres to the power-law is that most nodes have just a few links, although some have a tremendous number
of them. Another property is that the average distance between nodes is smaller than in a mesh-like network. A natural question
is how such a structural property performs in WDM networks. In this paper, we first investigate the property of the power-law
attribute of physical topologies for WDM networks. We compare the performance of WDM networks with mesh-like and power-law
topologies, and show that links connected to high-degree nodes are bottlenecks in power-law topologies. To relax this, we
introduce a concept of virtual fiber, which consists of two or more fibers, and propose its configuration method to utilize
wavelength resources more effectively. We compare performances of power-law networks with and without our method by computer
simulations. The results show that our method reduces the blocking probabilities by more than one order of magnitude. 相似文献
42.
This study proposes a new interactive multicriteria method for determining the best levels of the decision variables needed to optimize a stochastic computer simulation with multiple response variables. The method, called the Pairwise Comparison Stochastic Cutting Plane (PCSCP) method, combines good features from interactive multiple objective mathematical programming and response surface methodology. The major characteristics of the PCSCP method are: (1) it interacts progressively with the decision-maker (DM) to obtain her preferences, (2) it uses experimental design to explore the decision space adequately while reducing the burden on the DM, and (3) it uses the preference information provided by the DM and the sampling error in the responses to reduce the decision space. The mechanics of the method are illustrated with a numerical example. Some computational studies evaluating the method are also reported. 相似文献
43.
Min-Cheol Oh Sang-Shin Lee Sang-Yung Shin 《Quantum Electronics, IEEE Journal of》1995,31(9):1698-1704
A polarization converter using electrooptic (EO) polymer waveguides is proposed and it is simulated by a full vectorial beam propagation method (VBPM) for anisotropic medium. First, an efficient structure of poling electrodes is proposed for the fabrication of TE-mode poling-induced waveguides in EO polymer. For given electrode structures of both TE-mode and TM-mode waveguides, poling-induced dielectric tensors are calculated by the finite-element method to provide refractive index distribution, data for VBPM simulation. It is shown numerically that the poled TE and TM mode waveguides work efficiently as the corresponding polarization filters. Then, new poling electrodes are suggested to fabricate a waveguide device formed by connecting the TE and TM mode waveguides adiabatically with a slowly varying structure. This waveguide device has the optic axis slowly rotating as one moves along the propagation direction, so that it will act as polarization converter. VBPM simulation shows that the polarization of the guided mode rotates following the optic axis distribution. Polarization conversion is demonstrated successfully with high conversion efficiency and low excess loss 相似文献
44.
Kyeong-Sik Shin Kyeong-Kap Paek Jung-Ho Park Tae-Song Kim Byeong-Kwon Ju Ji Yoon Kang 《Electron Device Letters, IEEE》2007,28(7):581-583
In this letter, we examined whether the parasitic bipolar junction transistors (BJTs) in the MOSFET fabricated by the standard CMOS process can play a role as a fluorescence detector. To suppress the action of two vertical parasitic BJTs, the gate and n-well were tied in the parasitic BJTs, and the body node was connected to the drain. The proposed device was compared with the inherent and the parasitic diodes in the MOSFET. It had 100 times higher photocurrents than the diodes in the MOSFET. In addition, it was applied for the detection of the fluorescent signal, and could detect near 10 nM of Alexa 546. Therefore, CMOS-process-compatible parasitic BJTs can be used as a photodetector in an integrated fluorescence detector. 相似文献
45.
Understanding information sharing is an important challenge to modern organizations, and is likely to be increasingly considered when IT investment decisions are made world-wide. Our research study investigated the influence of cultural factors on information sharing in China. It was postulated that social network structures such as guanxi, Confucian dynamism, and collectivism could explain the degree to which information sharing took place between people in China. It was found that guanxi, Confucian dynamism, and collectivism all had a significant influence on information sharing. 相似文献
46.
A screening test was undertaken to isolate a microorganism that produced 5-oxoprolinase (without ATP-hydrolyzing). The 5-oxoprolinase (without ATP-hydrolyzing) activity (decyclization activity toward L-pyroglutamate) was found in a cell-free extract of Alcaligenes faecalis N-38A, newly isolated from a soil sample. The enzyme was purified as a homogeneous preparation. The molecular weight of the enzyme was estimated to be 47,000. The decyclization activity was specific for L-pyroglutamate, and independent of ATP and metal ions. The reaction was a reversible one, i.e., cyclization reaction of L-glutamate to yield pyroglutamate was identified. 相似文献
47.
MQ Fujita N Hashida M Shin H Nakanishi W Yoshihara K Aozasa 《Canadian Metallurgical Quarterly》1998,55(6):600-606
Poly(A)+ mRNA was isolated from leaves of potato plants (Solanum tuberosum L. cv. Desiree) according to standard protocols. This poly(A)+ mRNA was injected via glass microcapillaries into oocytes that were surgically removed from the African clawed toad Xenopus laevis. As a control, oocytes were either injected with H2O or remained untreated. Three days after injection the oocytes were analyzed by two electrode voltage clamping. Current voltage analysis revealed that a K+ channel from potato was functionally expressed in injected oocytes. The identity of this K+ channel was confirmed by its substrate specificity and a shift in the reversal potential. In particular, when the outside K+ concentration was increased the reversal potential of poly(A)+ injected oocytes shifted to more positive values. Furthermore, K+ outward currents declined when the outside K+ concentration was raised from 0.1 to 100 mM. Inward currents increased with an elevation of the K+ concentration. Several pharmaceuticals were tested for their potential to block this K+ channel. As a result, the channel was completely blocked by BaCl2. A three state reaction kinetic model was used to simulate the currents through the K+ transport protein as function of the extracellular K+ concentration. In particular, the simulation revealed current voltage relations that exactly matched the measured ones. Saturation of current voltage curves emerged from the simulation as a consequence of high extracellular potassium concentration. 相似文献
48.
Ali Hussein F. M. Khan Abdul Manan Baek Hangyeol Shin Buhyun Kim Youngshik 《Microsystem Technologies》2021,27(6):2481-2492
Microsystem Technologies - In this research a biologically inspired finger-like mechanism similar to human musculoskeletal system is developed based on Shape Memory Alloys (SMAs). SMA actuators are... 相似文献
49.
Shin K. Berry John W. Gramshaw 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1986,182(3):219-223
Summary The volatile compounds from the Maillard reaction in the glucose - glutamic acid system were analysed by combined gas chromatography - mass spectrometry. Of the 50 peaks detected, 42 components comprising 2 acids, 2 alcohols, 5 carbonyls, 2 esters, 4 lactones, 17 furans, 4 pyrazines and 3 pyrroles were identified, four of which tentatively. Decadien 2,4-al, 2-n-pentyl furoate, 2-(2-fury()-pyrazine. -nonalactone, 2-(2-fury()-5- or 6-methylpyrazine were previously not reported to occur in heated sugar - amino acid browning systems. The new compound, 5-formyloxymethyl-2-furfural has apparently not yet been recorded in the chemical literature.The compound 5-acetoxymethyl-2-furfural had an aroma close to that of bread whereas 5-formyloxymethyl-2-furfural exhibited a very faint sweet burnt aroma.
Taken in part from the Ph. D. thesis of the Senior Author 相似文献
Einige neue flüchtige Verbindungen aus der nicht-enzymatischen Bräunungsreaktion des Glucose-Glutaminsäure-Systems
Zusammenfassung Die flüchtigen Verbindungen aus der Maillardreaktion des Glucose-Glutaminsäure-Systems wurde mit Hilfe der Gaschromatographie/Massenspektrometrie analysiert. Von den 50 nachgewiesenen Peaks wurden 42 identifiziert: 2 Säuren, 2 Alkohole, 5 Carbonyle, 2 Ester, 4 Lactone, 17 Furane, 4 Pyrazine, 3 Pyrrole und 4 weitere provisorisch. Deca-2,4-dienal, 2-n-Pentylfluorat, 2-(2-Furyl)-pyrazin, -Nonalacton, 2-(2-Furyl)-5 oder -6-Methylpyrazin wurden bisher nicht in dem erhitzten Zucker-Aminosäuren-Bräunungssystem registriert. Die neue Verbindung 5-Formyloxymethyl-2-furfural ist anscheinend noch nicht in der chemischen Literatur festgestellt worden. Die Verbindung 5-Acetoxymethyl-2-furfural hat an ein Brot erinnerndes Aroma, während die 5-Formyloxymethyl-2-furfural-Verbindung ein sehr schwaches süßlich-verbranntes Aroma aufweist.
Taken in part from the Ph. D. thesis of the Senior Author 相似文献
50.
S.?H.?Yu H.?S.?Ryoo S.?K.?HwangEmail author D.?H.?Shin 《Metals and Materials International》2003,9(2):107-114
Grain boundary character distribution in equal-channel-angular pressed Zr was studied. Using a die design of 90°/20° and an
operation temperature of 350°C. The initial grain size of 20 μm was reduced to about 270 nm with 4 passes via route Bc. The grain growth kinetics of the recrystallized state was obtained by experiment and Monte-Carlo computer simulation, respectively,
which showed good agreement. Based on kinetics and morphological characteristics, it was concluded that the grain coarsening
mechanism was governed by normal grain growth. No sign of abnormal grain growth was detected either in the experiment or in
simulation despite taking into consideration anisotropy in grain boundary energy as well as its mobility. This indicates that
grain boundaries produced by severely deformed Zr are stable against explosive coarsening. The evolution characteristics of
the microstructure in the present ECA pressed and recrystallized Zr differed from those of cold rolled Ti in that the grain
boundary misorientation distribution and texture were rather stable during grain growth.
Jointly Appointed by the Center for Advanced Aerospace Materials
This article is based on a presentation made in the 2002 Korea-US symposium on the “Phase Transformations of Nano-Materials,”
organized as a special program of the 2002 Annual Meeting of the Korean Institute of Metals and Materials, held at Yonsei
University, Seoul, Korea on October 25–26, 2002. 相似文献