18106873
Camera Calibration with Two Arbitrary Coplanar Circles
In this paper, we describe a novel camera calibration method to estimate the extrinsic parameters and the focal length of a camera by using only one single image of two coplanar circles with arbitrary radius.
30329569
Lock-control System Using Face Identification
Security system is on the evolution as computer technology advances. One of the most important security is lock-control. This paper presents the PASSFACE system which is a lock-control system using face identification. There are three main processes in the face identification: 1) extraction of a face, 2) normalization of the size and the pose of the face image, 3) matching of facial features (eye, nose and mouth). In order to achieve high reliability, the normalization process searches inner corners of eyes and then applies affine transformation to the face image according to the positions of the detected inner corners. The matching is performed on facial features by template matching. Thresholds of the matching are determined by statistical estimation. When the system identifies a registered person, it unlocks the door. We have implemented this system and evaluated the usefulness of it.
11087494
3D head pose estimation without feature tracking
We present a robust approach to estimate the 3D pose of human heads in a single image. In contrast with other research, this method only makes use of the information about the skin region and the hair region of heads. At first, we use an efficient algorithm based on a perceptually uniform color system and fuzzy theory to extract the skin region and hair region, which are then used to detect faces in images. After that, the areas, the centers, and the axis of the least inertia both of the skin region and the hair region are calculated, which are then used to estimate the 3D pose of the head. We tested our method by estimating the 3D pose of a head from live video sequences. The three angles describing the three rotation elements of a head about X, Y and Z axes are extracted from each frame of the image sequence, which are then sent to a program that generates CG animations of a synthesized head in the estimated pose.
120321600
Visual line estimation from a single image of two eyes
This paper describes a conic-based algorithm for estimating visual line from a single monocular image. By assuming that the visual lines of the both eyes are parallel and the iris boundaries are circles, we propose a "two-circle" algorithm that can estimate the normal vector of the supporting plane of the iris boundaries, from which the visual line is calculated. Our new method does not use either the eye corners, or some heuristic knowledge about the structure of the eye. Another advantage of our algorithm is that a camera with an unknown focal length can be used without assuming the orthographical projection. This is a very useful feature because it allows one to use a zoom lens and to change the zooming factor whenever he or she likes. It also gives one more freedom of the camera setting because keeping the camera far from the eyes is not necessary in our method. The extensive experiments over simulated images and real images demonstrate the robustness and the effectiveness of our method.
206594758
Detecting Collusion Attacks in Security Protocols
Security protocols have been widely used to safeguard secure electronic transactions. We usually assume that principals are credible and shall not maliciously disclose their individual secrets to someone else. Nevertheless, it is impractical to completely ignore the possibility that some principals may collude in private to achieve a fraudulent or illegal purpose. Therefore, it is critical to address the possibility of collusion attacks in order to correctly analyse security protocols. This paper proposes a framework by which to detect collusion attacks in security protocols. The possibility of security threats from insiders is especially taken into account. The case study demonstrates that our methods are useful and promising in discovering and preventing collusion attacks.
18230
Indexable PLA for Efficient Similarity Search
Similarity-based search over time-series databases has been a hot research topic for a long history, which is widely used in many applications, including multimedia retrieval, data mining, web search and retrieval, and so on. However, due to high dimensionality (i.e. length) of the time series, the similarity search over directly indexed time series usually encounters a serious problem, known as the "dimensionality curse". Thus, many dimensionality reduction techniques are proposed to break such curse by reducing the dimensionality of time series. Among all the proposed methods, only Piecewise Linear Approximation (PLA) does not have indexing mechanisms to support similarity queries, which prevents it from efficiently searching over very large time-series databases. Our initial studies on the effectiveness of different reduction methods, however, show that PLA performs no worse than others. Motivated by this, in this paper, we re-investigate PLA for approximating and indexing time series. Specifically, we propose a novel distance function in the reduced PLA-space, and prove that this function indeed results in a lower bound of the Euclidean distance between the original time series, which can lead to no false dismissals during the similarity search. As a second step, we develop an effective approach to index these lower bounds to improve the search efficiency. Our extensive experiments over a wide spectrum of real and synthetic data sets have demonstrated the efficiency and effectiveness of PLA together with the newly proposed lower bound distance, in terms of both pruning power and wall clock time, compared with two state-of-the-art reduction methods, Adaptive Piecewise Constant Approximation (APCA) and Chebyshev Polynomials (CP).
11734040
Analyzing Security Protocols Using Association Rule Mining
Current studies to analyzing security protocols using formal methods require users to predefine authentication goals. Besides, they are unable to discover potential correlations between secure messages. This research attempts to analyze security protocols using data mining. This is done by extending the idea of association rule mining and converting the verification of protocols into computing the frequency and confidence of inconsistent secure messages. It provides a novel and efficient way to analyze security protocols and find out potential correlations between secure messages. The conducted experiments demonstrate our approaches.
8613363
Mining Frequent Itemsets for Protein Kinase Regulation
Protein kinases, a family of enzymes, have been viewed as an important signaling intermediary by living organisms for regulating critical biological processes such as memory, hormone response and cell growth. The unbalanced kinases are known to cause cancer and other diseases. With the increasing efforts to collect, store and disseminate information about the entire kinase family, it not only leads to valuable data set to understand cell regulation but also poses a big challenge to extract valuable knowledge about metabolic pathway from the data. Data mining techniques that have been widely used to find frequent patterns in large datasets can be extended and adapted to kinase data as well. This paper proposes a framework for mining frequent itemsets from the collected kinase dataset. An experiment using AMPK regulation data demonstrates that our approaches are useful and efficient in analyzing kinase regulation data.
16103789
A flexible image retrieval and multimedia presentation management system for multimedia databases
In today's fast-growing information age, multimedia data is becoming more and more common in daily applications, however this data is nearly useless if there is no computer-aided browsing, searching, and retrieving mechanism to obtain the desired contents. In this demonstration, we present a multimedia query and presentation management system for multimedia databases. It uses an unsupervised segmentation method for image and video feature extraction. A presentation design interface systems is provided that allows query results to be used to create multimedia presentations.