Ji Shen

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In this paper, we propose a new image quality assessment method based on a hybrid of curvelet, wavelet, and cosine transforms called hybrid no-reference (HNR) model. From the properties of natural scene statistics, the peak coordinates of the transformed coefficient histogram of filtered natural images occupy well-defined clusters in peak coordinate space,(More)
In order to support real-time video, audio and data communication among heterogeneous third generation (3G) handsets, 3G phones/terminals are required to support 3G-324M, the multimedia transmission protocol stack for 3G communication. This paper discusses some efficient approaches and experiences in the implementation of 3G-324M protocol stack.(More)
Next-generation network (NGN) is a new concept and becoming more and more important for future telecommunication networks. This paper illustrates five function layers of NGN architecture and discusses some end-to-end QoS (quality of service) issues for NGN (called NGNQoS). The five function layers are: (1) Application Layer that supports SIP protocol; (2)(More)
3G-324M is a multimedia transmission protocol designed for 3G communication environment. Meanwhile H.245 standard is a control protocol in 3G-324M and gives specific descriptions about terminal information messages in H.245 control channel as well as the procedures using them. The message syntax is defined using an external data representation standard(More)
We analyze the canonical nonlinear pricing model with limited information. A seller offers a menu with a finite number of choices to a continuum of buyers with a continuum of possible valuations. By revealing an underlying connection to quantization theory, we derive the optimal finite menu for the socially efficient and the revenue-maximizing mechanism. In(More)
We analyze a nonlinear pricing model with limited information. Each buyer can purchase a large variety, <i>d</i>, of goods. His preference for each good is represented by a scalar and his preference over <i>d</i> goods is represented by a <i>d</i>-dimensional vector. The type space of each buyer is given by a compact subset of <i>R<sup>d</sup></i>+ with a(More)
This paper proposes a collateral view of financial innovation: Many innovations are partly motivated by alleviating collateral constraints for trading (speculation or hedging). We analyze a model of investors with disagreement. The trading need motivates them to introduce derivatives, which are endogenously determined in equilibrium. In the presence of a(More)
This interactive poster session features seven research groups exploring how interactive, dynamic visualizations impact student learning. Six empirical studies report on promising designs for visualizations. These studies use logs of student interactions and embedded assessments to document the quality and trajectory of learning and to capture the cognitive(More)
In this paper, we propose a new general Quality Assessment method based on the curvelet transform, called Curvelet No-Reference (CNR) model, which can estimate levels of noise, blur and JPEG 2000 compression of natural images. The peak coordinate of the curvelet coefficient histogram occupies distinctive regions depending on how the image was modified from(More)