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91.
Dong Xue-Dong; Soh Cheong Boon; Gunawan Erry 《IMA Journal of Mathematical Control and Information》2005,22(1):1-11
This paper derives an algorithm for constructing codes overfinite fields of the algebraic integer ring of the cyclotomicfield Q(e2i/n) modulo irreducible elements with the norm p2,where n {3, 4, 5, 7, 8, 9, 11, 12, 13, 15, 16, 17, 19, 20,21, 24, 25, 27, 28, 32, 33, 35, 36, 40, 44, 45, 48, 60, 84},where p x n and p is a prime number. 相似文献
92.
A selective assay method for quantitation of amprenavir (agenerase) in human immunodeficiency virus type-1 infected patient serum or plasma using liquid chromatography-tandem mass spectrometry (LC-MS-MS) is described. Amprenavir and an internal standard (reserpine) are extracted by liquid-liquid extraction and chromatographically separated by a reversed-phase C18-analytical column. The triple quadrupole LC-MS-MS system is operated in the positive-ion mode and multiple reaction monitoring is used for drug quantitation. The method has been validated over the range of 0.05-10.0 microg/ml. The RSDs for the intra-day and inter-day determinations ranged from 5.3 to 6.1% and from 4.7 to 6.2%, respectively. The average assay accuracy at two different concentrations ranged from 96.0 to 103.0% and the extraction recovery of amprenavir was 90.8%. The lower limit of quantitation was 0.05 microg/ml. Using a short microbore column, the analysis was completed in less than 5 min. 相似文献
93.
A MAC protocol for new and handoff calls with a finite populationof users, rather than with an infinite user population as indynamic channel reservation scheme (DCRS), is considered. Similarto DCRS, we divide the wireless channels into shared channels andreserved channels. The handoff calls access any available channelwith probability of one, while the new calls access a sharedchannel with probability of one and access a reserved channel witha request probability. We propose three simpler formulae than thatused in the existing DCRS in setting the request probability. Inaddition, the handoff calls in our proposed protocol are allowedto queue in a finite buffer. To evaluate the system performance, amathematical model based on queuing theory, rather than asimulation method used in DCRS, is developed. It is a generalmodel that can be adopted for any types of request probabilitiesincluding DCRS. Suggestions of how to get the optimum values ofthe design parameters are also given. 相似文献
94.
This paper presents the problem of scheduling security teams to patrol a mass rapid transit rail network of a large urban city. The main objective of patrol scheduling is to deploy security teams to stations of the network at varying time periods subject to rostering as well as security-related constraints. We present several mathematical programming models for different variants of this problem. To generate randomized schedules on a regular basis, we propose injecting randomness by varying the start time and break time for each team as well as varying the visit frequency and visit time for each station according to their reported vulnerability. Finally, we present results for the case of Singapore mass rapid transit rail network and synthetic instances. 相似文献
95.
A simple and rapid gas chromatographic (GC) method has been developed for the simultaneous determination of combinations of acetaminophen, phenylpropanolamine hydrochloride, guaifenesin, pseudoephedrine hydrochloride, caffeine, chlorpheniramine maleate, and dextromethorphan hydrobromide in cough and cold tablets and syrups. After extraction of the analyte with alkaline ethyl acetate, 2 microL extract was injected (splitting ratio of 50:1) into a gas chromatograph equipped with a CBP1-M25-025 fused silica capillary column (25 m x 0.22 mm; film thickness, 0.25 microm). The column temperature was held at 150 degrees C for 5 min, increased to 175 degrees C at 3 degrees C/min, and increased to 270 degreesC at 10 degrees C/min. The temperatures of the flame ionization detector and injector were maintained at 300 degrees C. The GC method is inexpensive, rapid, accurate, and precise, and thus it can be used for routine analysis of tablet and syrup preparations in quality control laboratories of pharmaceutical companies. 相似文献
96.
Gunawan RC King JA Lee BP Messersmith PB Miller WM 《Langmuir : the ACS journal of surfaces and colloids》2007,23(21):10635-10643
We have developed surfaces for the selective presentation of biotinylated peptides and proteins in a background that resists nonspecific protein adsorption; controlled amounts of biotinylated poly(ethylene glycol) (MW 3400 Da; PEG3400) anchored to titanium-dioxide-coated surfaces via an adhesive tri-peptide sequence of L-3,4-dihydroxyphenylalanine (DOPA3-PEG3400-biotin; DPB) were incorporated within a DOPA3-PEG2000 background. Using optical waveguide lightmode spectroscopy, we found that the amounts of sequentially adsorbed NeutrAvidin and singly biotinylated molecules increased proportionally with the amount of DPB in the surface. Biotinylated peptides (MW approximately 2000 Da) were able to fill all three of the remaining avidin-binding sites, while only one molecule of biotinylated PEG5000 or stem cell factor bound to each avidin. The resulting biotin-avidin-biotin linkages were stable for prolonged periods under continuous perfusion, even in the presence of excess free biotin. Hematopoietic M07e cells bound to immobilized peptide ligands for alpha5beta1 (cyclic RGD) and alpha4beta1 (cylic LDV) integrins in a DPB-dose-dependent manner, with near-maximal binding to cylic LDV for surfaces containing 1% DPB. Multiple ligands were adsorbed in a controlled manner by incubating NeutrAvidin with the respective ligands in the desired molar ratio and then adding the resulting complexes to DPB-containing surfaces. Cell adhesion to surfaces containing both cylic LDV and cyclic RGD increased in an additive manner compared to that for the individual ligands. The bioactivity of adsorbed biotinylated stem cell factor was retained, as demonstrated by DPB-dose-dependent M07e cell adhesion and ERK1/2 activation. 相似文献
97.
The design of asymmetric coded frequency/phase modulation (FPM) is discussed. Designs for optimum asymmetric 2FSK/4PSK, 2FSK/8PSK and 2FSK/16PSK modulation schemes are derived and the effect of modulation index is studied. It is shown that an additional gain of 1.2-2.6 dB can be achieved by using optimised asymmetric modulation over that of a symmetric scheme 相似文献
98.
A Protocol for Multimedia CDMA Personal Communication Networks 总被引:2,自引:0,他引:2
In this paper, a joint CDMA/TDMA protocol has been proposed for integratedvideo-phone/voice/data traffic in personal communication networks (PCN). Thevideophone service is implemented according to H.261 standard. The concept ofdynamic boundary is adopted in both code and time domains to meet thedifferent requirements for videophone, voice and data traffic.Two mathematical analysis methods are adopted to evaluate the systemperformance. One is the traditional Markov analysis (TDMA), which is used tocalculate the average videophone and voice call blocking probabilities. Theother is Transient Fluid Analysis (TFA), which is adopted to evaluate the datadelay and channel utilization performance. Results show that two dynamicboundaries can be adjusted to achieve the optimal system performance, andsuggestions of how to adjust these boundaries are also given. 相似文献
99.
Christian J. Wijaya Suryadi Ismadji Hakun W. Aparamarta Setiyo Gunawan 《Molecules (Basel, Switzerland)》2021,26(21)
Due to its excellency and versatility, many synthesis methods and conditions were developed to produce HKUST-1 ([Cu3(BTC)2(H2O)3]n). However, the diversity of HKUST-1 was actually generated both in terms of characteristics and morphologies. Hence, the consistency of HKUST-1 characteristics and morphologies needs to be maintained. The statistical analysis and optimization provide features to determine the best synthesis condition. Here, a room-temperature coordination modulation method was proposed to maintain the morphology of HKUST-1 while reducing energy consumption. In addition, response surface methodology (RSM) was used to demonstrate the statistical analysis and optimization of the synthesis of HKUST-1. The molar ratio of ligand to metal, reaction time, and acetic acid concentration were studied to determine their effects on HKUST-1. The optimum HKUST-1 was obtained by the synthesis with a molar ratio of ligand to metal of 0.4703 for 27.2 h using 5% v/v acetic acid concentration. The statistical analysis performed a good agreement with the experimental data and showed the significance of three desired parameters on HKUST-1. The optimum HKUST-1 had the adsorption capacity of 1005.22 mg/g with a removal efficiency of 92.31% towards CV dye. It could be reused up to 5 cycles with insignificant decrease in performance. 相似文献
100.
This paper concerns with the fractional integrals,which are also known as the Riesz potentials.A characterization for the boundedness of the fractional integral operators on generalized Morrey spaces will be presented.Our results can be viewed as a refinement of Nakai’s [7]. 相似文献