10297562
Computational Models for the Helix Tilt Angle
The concept of hydrophobic imbalance and that of hydrophobic and hydrophilic centers are used along with side chain models in the computation of helix orientation and tilt angle in or near a membrane. Rotamer statistics are used to infer typical side chain positions and chain length for each amino acid, and the results are used in fast computation of helix orientation. Sliding windows are used to compute local tilt angles on long alpha-helices that defy idealized modeling and generate tilt angle profiles. Seven different procedures based on different formulas and hydrophobicity scales are used for comparison. These procedures generated very similar tilt angle profiles. These profiles provide insights into helix deformation, membrane destabilization, and similarity and differences between membrane proteins.
14172108
Context-dependent similarity
Attribute weighting and differential weighting, two major mechanisms for computing context-dependent similarity or dissimilarity measures are studied and compared. A dissimilarity measure based on subset size in the context is proposed and its metrization and application are given. It is also shown that while all attribute weighting dissimilarity measures are metrics differential weighting dissimilarity measures are usually non-metric.
216020825
Mean Shift, Mode Seeking, and Clustering
Mean shift, a simple iterative procedure that shifts each data point to the average of data points in its neighborhood, is generalized and analyzed in this paper. This generalization makes some k-m...
44320241
Convergence and Ordering of Kohonen's Batch Map
The convergence and ordering of Kohonen's batch-mode self-organizing map with Heskes and Kappen's (1993) winner selection are proved. Selim and Ismail's (1984) objective function for k-means clustering is generalized in the convergence proof of the self-organizing map. It is shown that when the neighborhood relation is doubly decreasing, order in the map is preserved. An unordered map becomes ordered when a degenerate state of ordering is entered, where the number of distinct winners is one or two. One strategy to enter this state is to run the algorithm with a broad neighborhood relation.
3320962
Track seeking hybrid fuzzy controller for the compact disc player
A hybrid track seeking fuzzy controller for an optical compact disc player is proposed. It is shown that the proposed hybrid fuzzy controller smoothes the applied voltage to the sled motor and improves the track seeking efficiency. The proposed hybrid fuzzy controller consists of three subsystems including parking time controller, driving force controller and parameter tuner. All three of subsystems are designed based on fuzzy inference. The hybrid fuzzy controller will on one hand drive the pickup head as fast as possible to the neighborhood of target track, it will on the other hand smoothly park the pickup head so that the fine seek controller can take over the control of pickup head.
15648291
An improved key distribution mechanism for large-scale hierarchical wireless sensor networks
Abstract Wireless sensor networks are often deployed in hostile environments and operated on an unattended mode. In order to protect the sensitive data and the sensor readings, secret keys should be used to encrypt the exchanged messages between communicating nodes. Due to their expensive energy consumption and hardware requirements, asymmetric key based cryptographies are not suitable for resource-constrained wireless sensors. Several symmetric-key pre-distribution protocols have been investigated recently to establish secure links between sensor nodes, but most of them are not scalable due to their linearly increased communication and key storage overheads. Furthermore, existing protocols cannot provide sufficient security when the number of compromised nodes exceeds a critical value. To address these limitations, we propose an improved key distribution mechanism for large-scale wireless sensor networks. Based on a hierarchical network model and bivariate polynomial-key generation mechanism, our scheme guarantees that two communicating parties can establish a unique pairwise key between them. Compared with existing protocols, our scheme can provide sufficient security no matter how many sensors are compromised. Fixed key storage overhead, full network connectivity, and low communication overhead can also be achieved by the proposed scheme.
28212950
Life is sharable: blogging life experience with RFID embedded mobile phones
Recent development and proliferation of mobile devices, wireless communication, and sensor technologies have prompted a new vision of social interactions in the world in which we inhabit. For example, the number of mobile phones that are capable of capturing users' spontaneous life experiences not only in pictures but also in audio and video clips is on the increase. In addition, captured experiences can be sent and shared with others over wireless networks such as WiFi, GSM, GPRS, EDGE, or recently commenced third-generation (3G) protocols. Other technology trends such as weblog and peer-to-peer communication provide a ubiquitous platform and a model of motivating users to share life experiences with other people. The hypothesis is that everyone can be an owner of a weblog which records their experience about place, people, and things that interest them. Initial form of peer-to-peer communication, centralized directory service, can help authors of weblogs attain widespread of popularity and increase the level of participation in this type of interaction. The convergence of these technologies provides new design opportunities for computer-mediated communications. The aim of this paper is to share our experiences in designing and implementing a novel physical prototype which incorporates peer-to-peer communication, weblog, RFID, wireless networking, and mobile phone technologies to enhance social quality of shared life experience.
31421692
Efficient resource allocation for SLA based wireless/wireline interworking
This paper proposes efficient resource allocation techniques for a domain-based wireless/wireline interworking architecture. Resource allocation is driven by the service level agreement (SLA). Each wireless domain can freely choose its internal resource management schemes to guarantee the customer access SLA (CASLA), while the border-crossing traffic is served by a DiffServ/MPLS core network according to the transit domain SLA (TRSLA). Specifically, we propose an engineered priority scheme for a cellular wireless domain, where the CASLA for each service class is met with efficient resource utilization and the interdomain TRSLA bandwidth requirement can be obtained conveniently. In the transit domain, the traffic load fluctuation from upstream access domains is tackled with an inter-TRSLA resource sharing technique, where the spare capacity from underloaded TRSLAs can be exploited by the overloaded TRSLAs to improve resource utilization.
6228406
Distributed and parallel execution of Java programs on a DSM system
The paper focuses on the loop-level parallelism of bytecode on a distributed shared memory (DSM) system, which is built on a cluster of multiprocessors. We define a new attribute called 'Loop Attribute' to record the information of Java loops. When first loading a Java program, our Java virtual machine, called ES-JVM, checks and analyzes the loops of the bytecode dynamically, handles the data dependence of loops, and records the information as the loop attributes. ES-JVM uses the virtual shared memory and synchronization mechanisms provided by the DSM system to maintain the memory consistency. Before ES-JVM interprets the loops of the bytecodes, it dispatches the workload of loops to the interpreter threads at all nodes according to the loop attributes and the number of threads. After distributed and parallel execution of the loops, ES-JVM continues to interpret the rest of the bytecodes of the Java program. Finally, ES-JVM saves the loop attributes in a new class file for the next run. Our research shows that distributed and parallel execution of loops of a Java program could improve performance.