摘要:
The present invention relates to a method of searching a metadata server that searches ubiquitous sensor network (USN) metadata servers in a distributed environment. The present invention stores location information on the metadata servers by using a location-server cluster and searches a location of a metadata server in which a specified resource metadata is stored, during a metadata searching request by a client. Accordingly, the present invention can provide a simple and consistent interface to the client using the metadata management servers in terms of the metadata servers and can improve the clarity of service development and can reduce the entire development costs and the maintenance and repair costs.
摘要:
A system and method for scalable status change detection in a network of nodes includes embedding node coordinate positions into a virtual map environment. A cluster of nodes are represented with a representative node to form a hierarchy of nodes and clusters where changes in a status of the representative node imply a status change in the nodes of the cluster. By selectively monitoring the representative nodes for the changes in status, the representative nodes create a capability for scalable monitoring of the network.
摘要:
Provided is preparation of poly(alkylene carbonate) by alternating copolymerization of carbon dioxide and epoxide. To be specific, provided are a method for preparing block or graft copolymers of the polymer compound and poly(alkylene carbonate) by alternating-copolymerization of an epoxide compound and carbon dioxide by using a metal (III) compound prepared from salen-type ligand with a quaternary ammonium salt as a catalyst in the presence of a polymer compound having a functional group of hydroxyl or carboxylic acid, and block or graft copolymers prepared by the method.
摘要:
Provided is preparation of poly(alkylene carbonate) by alternating copolymerization of carbon dioxide and epoxide. To be specific, provided are a method for preparing block or graft copolymers of the polymer compound and poly(alkylene carbonate) by alternating-copolymerization of an epoxide compound and carbon dioxide by using a metal (III) compound prepared from salen-type ligand with a quaternary ammonium salt as a catalyst in the presence of a polymer compound having a functional group of hydroxyl or carboxylic acid, and block or graft copolymers prepared by the method.
摘要:
A system and method for scalable status change detection in a network of nodes includes embedding node coordinate positions into a virtual map environment. A cluster of nodes are represented with a representative node to form a hierarchy of nodes and clusters where changes in a status of the representative node imply a status change in the nodes of the cluster. By selectively monitoring the representative nodes for the changes in status, the representative nodes create a capability for scalable monitoring of the network.
摘要:
A system and method for scalable status change detection in a network of nodes includes embedding node coordinate positions into a virtual map environment. A cluster of nodes are represented with a representative node to form a hierarchy of nodes and clusters where changes in a status of the representative node imply a status change in the nodes of the cluster. By selectively monitoring the representative nodes for the changes in status, the representative nodes create a capability for scalable monitoring of the network.
摘要:
There is provided a method for preparing a low-molecular weight poly(alkylene carbonate) of which the molecular weight and chain shape are precisely controlled, by introducing a phosphorous compound having a hydroxyl group as a chain transfer agent in order to regulate the molecular weight, in alternating copolymerizing an epoxide compound and carbon dioxide by using trivalent metal complex prepared from a Salen type ligand containing a quaternary ammonium salt, and a polymer prepared by the method.Since poly(alkylene carbonate) prepared according to the present invention includes a phosphate or phosphonate group in the polymer chain, it has flame-retarding property.
摘要:
There is provided a method for preparing a low-molecular weight poly(alkylene carbonate) of which the molecular weight and chain shape are precisely controlled, by introducing a phosphorous compound having a hydroxyl group as a chain transfer agent in order to regulate the molecular weight, in alternating copolymerizing an epoxide compound and carbon dioxide by using trivalent metal complex prepared from a Salen type ligand containing a quaternary ammonium salt, and a polymer prepared by the method.Since poly(alkylene carbonate) prepared according to the present invention includes a phosphate or phosphonate group in the polymer chain, it has flame-retarding property.
摘要:
A system and method for scalable status change detection in a network of nodes includes embedding node coordinate positions into a virtual map environment. A cluster of nodes are represented with a representative node to form a hierarchy of nodes and clusters where changes in a status of the representative node imply a status change in the nodes of the cluster. By selectively monitoring the representative nodes for the changes in status, the representative nodes create a capability for scalable monitoring of the network.