Abstract: Embodiments of this disclosure include a method and apparatus of dynamic spectrum allocation in coexisting heterogeneous wireless networks. A Mobile Station (MS) detects its own serving Access Point (AP) and a coexisting AP (cAP) of the serving AP, sends to the serving AP a service request message carrying a bandwidth demand and a cAP ID. The serving AP sends to a Dynamic Spectrum Allocation Module (DSAM) a spectrum request message carrying its own AP ID, the cAP ID and the spectrum demand. The DSAM allocates the spectrum dynamically using a dynamic spectrum allocation algorithm according to the spectrum demand, AP ID and cAP ID, and sends a spectrum allocation result to the serving AP, which allocates an appropriate bandwidth to the MS according to the spectrum allocation result. Thus, sharing spectrum dynamically between multiple coexisting wireless networks can be achieved, and spectrum utilization can be improved.

Abstract: A method for accessing a hybrid network including a wide area network and a distributed network, a gateway apparatus, a wireless terminal and a gateway communication system are disclosed for reducing the power consumption of the wireless terminal which is an access gateway. The method comprises: sensing by a gateway apparatus a relay request slot on a downlink common control channel of the wide area network; transmitting by a wireless terminal a relay request signal requesting to relay a data packet to be transmitted, in the relay request slot on the downlink common control channel; and if the relay request signal from the wireless terminal is sensed in the relay request slot, establishing by the gateway apparatus a connection with the wireless terminal in a distributed network environment.

Abstract: The present invention relates to a nematic liquid crystal compound and a liquid crystal composition exhibiting a fast response time over a wide temperature range comprising the same, and more particularly, to a liquid crystal composition with fast response characteristics, and having a high phase transition temperature of liquid crystal, and having a low driving voltage and a nematic phase in a wide temperature range, comprising a nematic liquid crystal compound having an isothionate group and at least one fluorine atom in an aromatic ring of a terminal group.

Abstract: The present invention relates to a nematic liquid crystal compound and a liquid crystal composition exhibiting a fast response time over a wide temperature range comprising the same, and more particularly, to a liquid crystal composition with fast response characteristics, and having a high phase transition temperature of liquid crystal, and having a low driving voltage and a nematic phase in a wide temperature range, comprising a nematic liquid crystal compound having an isothionate group and at least one fluorine atom in an aromatic ring of a terminal group.

Abstract: A process for modifying a nitride surface includes irradiating energized ion particles onto the nitride surface while blowing a reactive gas directly on the nitride surface under a vacuum condition. An aluminum nitride for a direct bond copper (DBC) can be obtained by forming a thin copper film on the thusly modified nitride.

Abstract: A thermal shock-resistant alumina-mullite composite material and a preparation method thereof which are capable of concurrently obtaining the compactness of the material and a mullite formation. The material is comprised of 4.about.30 weight % of one aluminum silicate selected from the group consisting of kaolinite, silimanite, and kyanite, 75.about.94 weight % of Al.sub.2 O.sub.3 based on the total amount of Al.sub.2 O.sub.3, and 0.5.about.6 weight % of an alkaline earth metal oxide, wherein the weight ratio of the alkaline earth metal oxide to SiO.sub.2 is 1:2.about.1:3. The composition is first sintered at a temperature of 1450.degree..about.1650.degree. C. for 1.about.5 hours, then cooled down to 1000.degree. C., and then crystallized at a temperature of 1200.degree..about.1500.degree. C. for 1.about.20 hours. This composition is usable to a maximum temperature 300.degree. C.