摘要:
A method and apparatus is disclosed whereby the scheduling of network transmissions in a wireless backhaul network is determined using a cross-layer optimization algorithm. In a first embodiment, the algorithm assumes a good MAC layer transmit schedule has been provided and computes optimal network layer routes as well as transmit beam patterns and transmit powers in a semi-distributed manner. According to this embodiment, the optimization goal is the throughput from each access point, or node in the network, to the core network. In another embodiment, an independent set of transmitting nodes is determined at the MAC layer in a way such that no link in the set interferes with another link and no link is scheduled to transmit and receive at the same time. According to this embodiment, a column generation algorithm is used to find a maximal weighted independent set and to achieve optimal network transmission throughput.
摘要:
A method and apparatus for medium access control in a wireless ad hoc network is disclosed that takes advantage of physical layer properties to jointly and collectively optimize in a distributed fashion transmission parameters such as beam-patterns and transmit powers of all active links in the network. To resolve signal transmission contention, each potential link is associated with a persistence parameter and the persistence parameter is adapted locally, with no central control, to provide medium access for transmissions. Where a node contending for a transmission slot is unable to optimize its transmission parameters due to an invalidity condition or infeasibility condition, the persistence parameter is updated, preferably so as to reduce the probability of such conditions.
摘要:
The present invention relates to protein tyrosine phosphatase (PTP) and a method for preparing the same, precisely, a method for expressing PTP active domain with high activity and stability without help of a fusion protein, by using computer based protein structure prediction technique. PTP prepared by the method of the present invention can be effectively used as a protein for high efficiency drug screening for the development of a novel drug, as an antigen protein for the construction of a selective antibody and as a protein for the studies of PTP structure and functions.
摘要:
A pattern wheel driver is provided. The pattern wheel driver includes a rotatable pattern wheel with patterned regions repeatedly formed on the pattern wheel. Each of the patterned regions has a plurality of patterns. Each of the plurality of patterns has a different width. The pattern wheel driver also includes a detector for detecting the plurality of patterns, mounted at a position where the patterned regions of the pattern wheel pass when the pattern wheel rotates. The pattern wheel driver also includes an encoder for producing a signal indicating whether the pattern wheel rotates in a forward direction or a reverse direction based on signals produced by the detector.
摘要:
The inventive indene derivatives of formula (I) are capable of selectively modulating the activities of peroxisome proliferator activated receptors (PPARs), causing no adverse side effects, and thus, they are useful for the treatment and prevention of disorders modulated by PPARs, i.e., metabolic syndromes such as diabetes, obesity, arteriosclerosis, hyperlipidemia, hyperinsulinism and hypertension, inflammatory diseases such as osteoporosis, liver cirrhosis and asthma, and cancer.
摘要:
A method and apparatus for distributed routing at the network layer of a network is disclosed that integrates contention resolution properties from the MAC layer. In one embodiment, an energy constraint is used in routing at the network layer of a network to determine a first parameter representing the optimal maximum lifetime of a sensor network. If a network link for a transmission is idle, the node may then contend at the MAC layer of the network for a transmission slot across that link. During this contention period, each node is assigned a penalty parameter that is used to represent the probability of a transmission colliding with another transmission across a link in a contention region. As a result of this contention period, network traffic is transmitted from sensor nodes.