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The new measurement scheme of IP performance metrics is proposed for the mobile network in heterogeneous wireless network environment. In the proposed scheme, when Mobile Nodes (MNs) inside the mobile network needs to understand the condition of multiple communication paths outside the mobile network, they can get IP performance metrics, such as delay, jitter, bandwidth, packet loss, etc., irrespective of the presence or absence of measurement functionality. At the same time, the proposed scheme does not require the MN to be involved in measuring IP performance metrics. The Multihomed Mobile Router (MMR) with heterogeneous wireless interfaces measures IP performance metrics on behalf of the MNs inside the mobile network. Then, MNs can get measured IP performance metrics from the MMR using L3 messages. The proposed scheme can reduce burden and power consumption of MNs with limited resource and battery power since MNs don't measure IP performance metrics directly. In addition, it can reduce considerably traffic overhead over wireless links on multiple measurement paths since signaling messages and injected testing traffic are reduced. 相似文献
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The use of repeater for the support of high rate data transmission and the extension of cell coverage is imperative for the Wibrc system,which based on the IEEE 8M.16e standardization.Generally,if the separation between transmitting and receiving antennas isnot sufficient,the oscillation of repeater and the interference due to the feedback signals from original transmitted signal may be ocerur.Hence,the Interference Cancellation System(ICS)should be implemented as the important part of the repeater system far the mobile cellular systems in order to eliminate unwanted signals from the corruptW signals in the receiver.In this paper,we propose an adaptive technique for the Least Mean Square(LMS)-based interference cancellation methods by changing the step size according to the variation of channel environment in order to improve the performance degradation which oceuurs by using the fixed step size approach.Simrlatim results show that the proposed sclxme attains a little lower Berafor Rate(BER)performance and much faster convergence speed compared to the conventional LMS-based interference cancellation techniques.The proposed scheme can be applied to other Orthogonal Frequency Division Multiple(OFDM)-based cellular systems and also be expected to achieve a similar performance improvement to W17-advanced system,which is called as the next generation mobile communication standards. 相似文献
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This paper considers a production and inventory problem in which the utility or potential of an item gradually reduces with the passage of time, such as grain, photographic film and electronic component. The aim of this paper is to determine the production rate of the decaying item in a way that minimizes the current value of total cost using optimal control theory. For the model developed, a computational procedure of finding an optimal solution is developed. The steady-state solution and the properties of the optimal solution for the case of constant rate of decay are discussed. 相似文献
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Kyo-Hong CHOI Kwon-Koo CHO Gyu-Bong CHO Hyo-Jun AHN Ki-Won KIM Yoo-Young KIM 《材料科学与工程学报》2007,25(6):886-891
Several researches have been reported about the characteristic of β-Ga2O3 nanowires which was synthesized on nickel oxide particle. But indeed, recent researches about synthesis of β-Ga2O3 nanowires on oxide-assisted transition metal are limited to nickel or cobalt oxide catalyst. In this work, Gallium oxide (β-Ga2O3 ) nanowires were synthesized by a simple thermal evaporation method from gallium powder in the range of 700 - 1000℃ using the iron, nickel, copper, cobalt and zinc oxide as a catalyst, respectively. The β-Ga2O3 nanowires with single crystalline without defects were successfully synthesized at the reaction temperature of 850, 900 and 950℃ in all the catalysts. But optimum experimental condition in synthesis of nanowires varied with the kind of catalyst. As increasing synthesis temperature,the morphology of gallium oxide nanowires changed from nanowires to nanorods, and its diameter increased. From these results, we could be proposed that the growth mechanism of β-Ga2O3 nanowires was changed with synthesis temperature of nanowires. Microstructure and morphology of Synthesized nanowire was characterized by HR-TEM, FE-SEM, EDX and XRD. 相似文献
18.
To increase battery life in IEEE 802.16e systems, it is essential to efficiently manage energy in mobile stations. The sleep-mode operation in power management helps to increase the life of a station by saving energy consumption. In power management, there are two important performance metrics energy consumption and the response delay of awakening medium access control (MAC) service data unit (SDU). While in a base station (BS) initiation of awakening, the two performance metrics should be simultaneously considered, in a mobile subscriber station (MSS) initiation of awakening, the response delay is not considered because it is self-operational. There performance metrics are affected by the minimum sleep interval (Tmin), the maximum sleep interval (Tmax), and the average interarrival time of awakening MAC SDUs (TI) during sleep-mode operation. Therefore, it is imperative to evaluate the two initiations of awakening depending on TI. To reach a fuller understanding of the performance, this paper shows an analytical mode and simulations results for the standard sleep-mode operation in the IEEE 802.16e MAC. 相似文献
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F. R. DEL VALLE M. ESCOBEDO P. RAMOS S. DE SANTIAGO R. BECKER H. BOURGES K. C. RHEE Y. R. CHOI M. VEGA J. PONCE 《Journal of food science》1986,51(5):1242-1244
Cottonseed/soybean blends (50/50) were ground in an Alpine pin mill with or without previous cooking in a Brady low-cost extruder. Free gossypol decreased with increasing amount of water added prior to extrusion and number of passes through the extruder. Available lysine increased with decreasing amount of added water but was unaffected by number of passes through the extruder. Type of soybean raw material utilized had no effect on free gossypol. Blends prepared from defatted cottonseed meal, however, had lower free gossypol than those made from cottonseed kernels. A blend similar to full-fat soy flour but of lower cost was prepared from unextruded 50% defatted cotton-seed meal/50% extruded soybean flakes, without added water, and ground in the Alpine mill. 相似文献
20.
SEONG- JIN CHOI SAHN NAHM JAE-DONG BYUN KYUNG-SOO SUH HWACK JOO LEE HYUN RYU 《Journal of Materials Science Letters》1997,16(10):785-787
Abstracts are not published in this journal
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献