Abstract: Described herein are methods for rendering biodegradable a plastic material that is not itself biodegradable, by blending the plastic material with a carbohydrate-based polymeric material that is formed from one or more starches, and a plasticizer (e.g., glycerin). The carbohydrate-based polymeric material is less crystalline than the starting starch materials, e.g., being substantially amorphous, and having a crystallinity of no more than 20%. Third party testing shows blends of such materials render the entire blend biodegradable, believed to be due to the low crystalline substantially amorphous carbohydrate-based polymeric material breaking the hygroscopic barrier associated with the non-biodegradable plastic material, so that when blended together, both the plastic material and the carbohydrate-based polymeric material are biodegradable.

Abstract: Described herein are strength characteristics and biodegradation of articles produced using one or more petrochemical-based polymers and one or more carbohydrate-based polymers. A compatibilizer can optionally be included in the article. In some cases, the article can include a film or bag.

Abstract: Described herein are strength characteristics and biodegradation of articles produced using one or more petrochemical-based polymers and one or more carbohydrate-based polymers. A compatibilizer can optionally be included in the article. In some cases, the article can include a film or bag.

Abstract: Described herein are strength characteristics and biodegradation of articles produced using one or more petrochemical-based polymers and one or more carbohydrate-based polymers. A compatibilizer can optionally be included in the article. In some cases, the article can include a film or bag.

Abstract: Described herein are strength characteristics and biodegradation of articles produced using one or more petrochemical-based polymers and one or more carbohydrate-based polymers. A compatibilizer can optionally be included in the article. In some cases, the article can include a film or bag.

Abstract: Described herein are strength characteristics and biodegradation of articles produced using one or more petrochemical-based polymers and one or more carbohydrate-based polymers. A compatibilizer can optionally be included in the article. In some cases, the article can include a film or bag.

Abstract: A method and an apparatus for propagating a message in a social network are disclosed. A method for propagating a message in a social network according to an embodiment of the invention can include: calculating a degree of connectivity of each user; calculating a propagation capability of each user by using the calculated degree of connectivity and a probability of distribution; choosing target users for propagating a message by using the propagation capability of each user; and propagating the message to nodes of the chosen target users.

Abstract: A key-based method for controlling access in a social network service includes: generating a core key and sub keys by segmenting a master key that is unique to a file owner, with the sub keys assigned differently to multiple groups that are divided according to trust level and relationship type; determining the group to which a file requester belongs by using at least one of a friend list of the file requester, a trust level between the file requester and the file owner, and a friend list of the file owner, and distributing a sub key corresponding to the determined group to the file requester, when the file requester requests a key distribution; and determining whether or not access to a file of the file owner is authorized by using the sub key distributed to the file requester and the core key, when the file requester requests the file.

Abstract: A method and an apparatus for propagating a message in a social network are disclosed. A method for propagating a message in a social network according to an embodiment of the invention can include: calculating a degree of connectivity of each user; calculating a propagation capability of each user by using the calculated degree of connectivity and a probability of distribution; choosing target users for propagating a message by using the propagation capability of each user; and propagating the message to nodes of the chosen target users.

Abstract: A method for providing a social network service includes: (a) setting an access threshold value for a content belonging to a content owner and a weight value for one or more communities of which the content owner is a member; (b) extracting a community of which a content requester is a member from among the communities of which the content owner is a member, when a request for the content is received from the content requester, and calculating an activity value of the content requester for the extracted community; (c) calculating a reputation value for the content requester by using one or more of a number of the extracted communities, a weight value set for the extracted communities, and the calculated activity value; and (d) providing the content requester with authorization to access the content according to a comparison result between the reputation value and the access threshold value.

Abstract: A key-based method for controlling access in a social network service includes: generating a core key and sub keys by segmenting a master key that is unique to a file owner, with the sub keys assigned differently to multiple groups that are divided according to trust level and relationship type; determining the group to which a file requester belongs by using at least one of a friend list of the file requester, a trust level between the file requester and the file owner, and a friend list of the file owner, and distributing a sub key corresponding to the determined group to the file requester, when the file requester requests a key distribution; and determining whether or not access to a file of the file owner is authorized by using the sub key distributed to the file requester and the core key, when the file requester requests the file.