Pohang University of Science and Technology Foundation

K-1 Ecotech Co., Ltd.

Jong Sang Kim

Sangho Lee

Chang Hyun Choi

Dae Hyun No

Heejin Park

A circular filtering disc and a filter device having the filtering disc. The filtering disc includes a circular partition plate having an inner hub and an outer rim, with radial inlet holes formed in the outer rim and introducing water to the partition plate, and a vertical outlet hole formed in the center of the inner hub and discharging pure water; and a filter fabric placed on or below the partition plate, wherein water supplied to the filtering disc passes through the filter fabric and becomes concentrated at the vertical outlet hole, and is discharged from the filtering disc through the vertical outlet hole. In the filter device, raw water is supplied through the circumferential edges of the circular filtering discs stacked on top of one another in the filter device and is filtered prior to being discharged from the filter device through the center of the filtering discs.

Circular filtering disc and filter device having the same

Methods and apparatuses for providing DRM interoperability are provided. Proxy re-encryption technique using bilinear map is used, and the same content can be used in different devices. According to the method of providing DRM interoperability includes in proxy agent with respect to digital rights management (DRM) service providers and device which supports predetermined DRM, first DRM service provider, second DRM service provider, the proxy agent, and the device identify each other, and proxy re-encrypt an interoperable content (IC) and provide the IC to the device. The IC is second-level encrypted by using a key of the first DRM service provider, and the proxy re-encryption is performed by using a proxy key generated from proxy key information provided from the first DRM service provider and the second DRM service provider. Therefore, a problem in which interoperability cannot be guaranteed since a DRM technique depends on a service provider is resolved.

Growing community of inventors

Gyeongbuk, South Korea

Jong Sang Kim