This paper presents a mathematical model that analyzes the throughput of the IEEE 802.11b distributed coordination function (DCF) with the collision aware rate adaptation (CARA) algorithm. IEEE 802.11 WLANs provid...This paper presents a mathematical model that analyzes the throughput of the IEEE 802.11b distributed coordination function (DCF) with the collision aware rate adaptation (CARA) algorithm. IEEE 802.11 WLANs provide multiple transmission rates to improve system throughput by adapting the transmission rate to the current channel conditions. The system throughput is determined by some stations using low transmission rates due to bad channel conditions. CARA algorithm does not disturb the existing IEEE 802.11b formats and it can be easily incorporated into the commercial wireless local area networks (WLAN) devices. Finally, we verify our findings with simulation.展开更多
Using the mRNA from the fruit of Cara Cara as the template, the cDNA of phytoene synthase (PSY) gene was amplified by reverse transcription polymerse chain reaction (RT-PCR). Sequence analysis indicated that the c...Using the mRNA from the fruit of Cara Cara as the template, the cDNA of phytoene synthase (PSY) gene was amplified by reverse transcription polymerse chain reaction (RT-PCR). Sequence analysis indicated that the cDNA was of 1 520 bp, which had an open reading frame of 1 308 bp and encoded a protein of 436 amino acids. The homology analysis showed that PSY of Cara Cara shared high similarities of nucleotides and deduced amino acids with those in other plants up to more than 75 and 70%, respectively. A putative signal transit peptide for plastid targeting was found in the N-terminal region of PSY. The mature forms of PSY included a transmembrane (TM) domain. The recombinant plasmid pET-CitPSY was constructed by subcloning the full coding sequence of PSY cDNA into pET-28 (+). After transformation of E. coli BL21 and induced by 1 mmol L^-1 isopropyl-β-D-thiogalacropyranoside (IPTG), the fusion protein (6× His-PSY) with 52 kD was produced at a high level by prokaryotic expression system. The results of Western blot demonstrated that the fusion protein (6× His-PSY) could be recognized by anti-6 × His monoclonal antibody. The study could establish a basis for molecular improvement of Citrus fruit colors.展开更多
The purpose of this paper is to combine the estimation of output price risk and positive mathematical programming (PMP). It reconciles the risk programming presented by Freund with a consistent estimate of the constan...The purpose of this paper is to combine the estimation of output price risk and positive mathematical programming (PMP). It reconciles the risk programming presented by Freund with a consistent estimate of the constant absolute risk aversion (CARA) coefficient. It extends the PMP approach to calibration of realized production outputs and observed input prices. The results of this specification include 1) uniqueness of the calibrating solution, 2) elimination of the tautological calibration constraints typical of the original PMP procedure, 3) equivalence between a phase I calibrating solution and a solution obtained by combining phase I and phase II of the traditional PMP procedure. In this extended PMP framework, the cost function specification involves output quantities and input prices—contrary to the myopic cost function of the traditional PMP approach. This extension allows for a phase III calibrating model that replaces the usual linear technology with relations corresponding to Shephard lemma (in the primal constraints) and the marginal cost function (in the dual constraints). An empirical example with a sample of farms producing four crops illustrates the novel procedure.展开更多
文摘This paper presents a mathematical model that analyzes the throughput of the IEEE 802.11b distributed coordination function (DCF) with the collision aware rate adaptation (CARA) algorithm. IEEE 802.11 WLANs provide multiple transmission rates to improve system throughput by adapting the transmission rate to the current channel conditions. The system throughput is determined by some stations using low transmission rates due to bad channel conditions. CARA algorithm does not disturb the existing IEEE 802.11b formats and it can be easily incorporated into the commercial wireless local area networks (WLAN) devices. Finally, we verify our findings with simulation.
文摘Using the mRNA from the fruit of Cara Cara as the template, the cDNA of phytoene synthase (PSY) gene was amplified by reverse transcription polymerse chain reaction (RT-PCR). Sequence analysis indicated that the cDNA was of 1 520 bp, which had an open reading frame of 1 308 bp and encoded a protein of 436 amino acids. The homology analysis showed that PSY of Cara Cara shared high similarities of nucleotides and deduced amino acids with those in other plants up to more than 75 and 70%, respectively. A putative signal transit peptide for plastid targeting was found in the N-terminal region of PSY. The mature forms of PSY included a transmembrane (TM) domain. The recombinant plasmid pET-CitPSY was constructed by subcloning the full coding sequence of PSY cDNA into pET-28 (+). After transformation of E. coli BL21 and induced by 1 mmol L^-1 isopropyl-β-D-thiogalacropyranoside (IPTG), the fusion protein (6× His-PSY) with 52 kD was produced at a high level by prokaryotic expression system. The results of Western blot demonstrated that the fusion protein (6× His-PSY) could be recognized by anti-6 × His monoclonal antibody. The study could establish a basis for molecular improvement of Citrus fruit colors.
文摘The purpose of this paper is to combine the estimation of output price risk and positive mathematical programming (PMP). It reconciles the risk programming presented by Freund with a consistent estimate of the constant absolute risk aversion (CARA) coefficient. It extends the PMP approach to calibration of realized production outputs and observed input prices. The results of this specification include 1) uniqueness of the calibrating solution, 2) elimination of the tautological calibration constraints typical of the original PMP procedure, 3) equivalence between a phase I calibrating solution and a solution obtained by combining phase I and phase II of the traditional PMP procedure. In this extended PMP framework, the cost function specification involves output quantities and input prices—contrary to the myopic cost function of the traditional PMP approach. This extension allows for a phase III calibrating model that replaces the usual linear technology with relations corresponding to Shephard lemma (in the primal constraints) and the marginal cost function (in the dual constraints). An empirical example with a sample of farms producing four crops illustrates the novel procedure.