An unconstrained dual approach to solving Karmarkar-type linear programs using conventional barrier functions

This paper proposes an unconstrained dual approach and an efficient algorithm for solving Karmarkar-type linear programming problems. Conventional barrier functions are incorporated as a perturbation term in the derivation of the associated duality theory. An optimal solution of the original linear program can be obtained by solving a sequence of unconstrained concave programs, or be approximated by solving one such dual program with a sufficiently small perturbation parameter. A globally convergent curved-search algorithm with a quadratic rate of convergence is designed for this purpose. Based on our testing results, we find that the computational procedure is very efficient and can be a viable approach for solving linear programming problems.     

Delay Time Measurement and Comparison of Protection Strategies with One-Link Failed Domestic Optical Fiber Networks in Taiwan

In this paper, we study the protection strategies of domestic optical fiber networks in Taiwan. Delay time experiment of two one-link failed cases are also reported and compared. We can get best protection strategy and bypass the optical transmission signal at shortest delay time.     

Analysis of a 32-Channal Benes Switching Network Including an SDM/WDM Router

An spatial division multiplexing/wavelength division multiplexing router is designed for applying in a fiber-optical wide area network. Our comparison shows various spans of the good SDM/WDM WAN using the SOA based router.     

Polypeptides with High Zwitterion Density for Safe and Effective Therapeutics

The commonly used “stealth material” poly(ethylene glycol) (PEG) effectively promotes the pharmacokinetics of therapeutic cargos while reducing their immune response. However, recent studies have suggested that PEG could induce adverse reactions, including the emergence of anti‐PEG antibodies and tissue histologic changes. An alternative stealth material with no or less immunogenicity and organ toxicity is thus urgently needed. We designed a polypeptide with high zwitterion density (PepCB) as a stealth material for therapeutics. Neither tissue histological changes in liver, kidney, or spleen, nor abnormal behavior, sickness or death was induced by the synthesized polymer after high‐dosage administration for three months in rats. When conjugated to a therapeutic protein uricase, the uricase–PepCB bioconjugate showed significantly improved pharmacokinetics and immunological properties compared with uricase–PEG conjugates.     

Synthetic and modified isoflavonoids. X. Synthesis of 2-ethyl and 2-propyl homologues of pseudobaptigenin

Homologues of pseudobaptigenin containing ethyl and propyl groups in position 2 have been synthesized. The structures of the new compounds have been comfirmed by PMR.KIEN, Karakalpak Division, Academy of Sciences of the Republic of Uzbekistam, Nukus. Taras Shevchenko Kiev University. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 334–337, May–June, 1994.     

Process engineering of high-ethanol-tolerance yeast for the manufacture of ethanol

Applied Biochemistry and Biotechnology - Inhibitory effects of ethanol and glucose on a high-ethanol-tolerance yeast strain (fusion product ofSaccharomyces diastaticus andSaccharomyces uvarum)...     

The impact of loyalty and promotion effects on retention rate

Researching customer retention rates is made difficult because of the lack of suitable systems with which to measure it. From a first-order Markov brand-switching model, serial equations are derived to estimate the retention rate using market share and loyalty. To explore the impact of loyalty and promotion programme on retention rate, data from five leading brands for three product categories were obtained to fit the developed model. Findings suggest that: (1) when the loyalty effect remains unchanged over a period of time, the greater the effect of a promotion programme, the greater the retention rate; (2) when the promotion effects among brands are similar, the retention rate varies depending on level of loyalty; and (3) when the proportion of loyal customers is high, the proportion of potential switchers affected by promotion programmes is low. In this case, the impact of a promotion programme on the retention rate is not significant. This model successfully demonstrates how the Markov brand-switching model can be employed to estimate a measure of retention rate from consumer panel data as well as to better understand how promotion affects loyalty, switching behaviour, and retention rate.