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With the increasing versatility of CMR, further understanding of intrinsic contractility of the myocardium can be achieved by performing subject-specific modeling by integrating structural and functional information available. The recent introduction of the virtual tagging framework allows for visualization of the localized deformation of the myocardium based on phase contrast myocardial velocity mapping. The purpose of this study is to examine the use of a non-linear, Kernel-Partial Least Squares Regression (K-PLSR) predictive motion modeling scheme for the virtual tagging framework. The method allows for the derivation of a compact non-linear deformation model such that the entire deformation field can be predicted by a limited number of control points. When applied to virtual tagging, the technique can be used to predictively guide the mesh refinement based on the motion of the coarse grid, thus greatly reducing the search space and increasing the convergence speed of the algorithm. The effectiveness and numerical accuracy of the proposed technique are assessed with both numerically simulated data sets and in vivo phase contrast CMR velocity mapping from a group of 7 subjects. The technique presented has a distinct advantage over the conventional mesh refinement scheme and brings CMR myocardial contractility analysis closer to routine clinical practice. [ABSTRACT FROM AUTHOR]

In RFID system, one of the problems that we must solve is the collision between tags that may occur when a reader attempts to read a number of tags simultaneously. Most of the popular anti-collision algorithms are based on the ALOHA-type algorithm, which are simple and show good performance when the number of tags to read is small. However, for ALOHA-type algorithms the time required to read the tags generally increases exponentially as the number of tag increases. Thus, they are not very efficient when the number of tags to read is large. In the paper, we propose a new anti-collision algorithm called Enhanced Dynamic Framed Slotted ALOHA (EDFSA) in which the time required to read the tags increases linearly with the number of tags. The proposed algorithm estimates the number of unread tags first and adjusts the number of responding tags or the frame size to give the optimal system efficiency. Simulation results show that the proposed algorithm improves the reading rate of data of the tags by 85~100% compared to the conventional algorithms. [ABSTRACT FROM AUTHOR]

Radio Frequency Identification (RFID) system is an important technology in ubiquitous computing environment. RFID system should be compatible with most RFID system applications to support the ubiquitous computing environment. Recently, researchers had studied about RFID standardization. After all, EPCglobal Class-1 Gen-2 (C1G2) RFID is selected as an international standard of RFID systems. Unfortunately, it has fatal security problems to be vulnerable to information leakage and traceability since a tag of EPCglobal C1G2 emits its fixed ID(EPC) without hiding or modifying. A main goal of our work is to propose the secure protocol well suitable for EPCglobal C1G2. First of all, our protocol exactly follows RFID standard with only current capabilities of a tag approved in the standard, assuring that our protocol is secure against impersonation, information leakage, and traceability etc. [ABSTRACT FROM AUTHOR]

This paper presents an embedding framework for myocardial velocity processing with MRI based on a hollow, semi-spherical template. The relationship between vector bundle and manifold mapping is analysed and three different mapping methods that include tangent mapping, normal mapping, and normal-tangent mapping are assessed for their practical value of myocardial contractility analysis. The proposed method provides a basis for consistent volume matching and vector correspondence, in addition to the ease of calculating biomechanical indices such as radial, circumferential and longitudinal strain rates without the concern of boundary effects. Detailed analysis results with both synthetic and in vivo MR velocity data sets are provided. [ABSTRACT FROM AUTHOR]

Radio Frequency identificiation (RFID) will become an important technology in remotely object identification systems. However, the use of RFID tags may create new threats to the security and privacy of individuals holding RFID tags. These threats bring several problems which are information leakage of a tag, location trace of individuals and impersonation of a tag. Low-cost RFID systems have much restrictions such as the limited computing power, passive power mechanism and low storage space. Therefore, the cost of tag's computation should be considered as an important factor in low-cost RFID systems. We propose an authentication protocol, OHLCAP which requires only one one-way hash function operation and hence is very efficient. Furthermore, our protocol is suitable to ubiquitous computing environment. [ABSTRACT FROM AUTHOR]

The intelligent dual-reactor with the current controlled inverter, which was operated based on the current controlled algorithm, was suggested in this paper. It could limit the fault current from the fault accident as well as compensate the reactive power of the grid, irrespective of the non-linear load type or its variation. The suggested equipment consisted of the dual-reactor with a power switch and the full bridge inverter. The operation of this equipment could be divided into the normal state and the short-circuit state. The operational characteristics of the proposed intelligent dual-reactor connected with the current controlled inverter for both the normal state and the short-circuit state were analyzed from the simulation results. Keyword:dual-reactor, current controlled inverter, fault current, reactive power [ABSTRACT FROM AUTHOR]

An effective matrix operation is critical to process 2-D DCT. This paper presents a hierarchically controlled SIMD array (HCSA) well suited to matrix computations, in which a conventional 2-D torus is enhanced with the hierarchical organization of control units and the global data buses running across the rows and columns. The distinguished features of the HCSA are the diagonally indexed concurrent broadcast and the efficient data exchanges among PEs through either row or column broadcast. Therefore, the HCSA can provide significant improvement on computation steps of DCT. For the performance evaluation, an algorithmic mapping method is used and the number of computation steps is analytically compared with semisystolic architecture. [ABSTRACT FROM AUTHOR]

The 1980s were widely heralded as a decade of democratization throughout the world. Scholarly arguments about the affinity between "bureaucratic-authoritarian regimes" and rapid economic development gave way to analysis of the "transitions to democracy." This paper examines the movement toward political liberalization in South Korea during this past decade. It begins by examining how the Republic of Korea's (ROK) pattern of "dependent development" and semiperipheral status in the world constrains its internal politics and class structures. Understanding the international political-economic context also illuminates the structural openings that can be used by the proponents of democracy. The main focus of this paper is on the societal forces within South Korea that affect its politics. The key role of the ROK state in directing the "economic miracle," and the relationship that developed among the state, capital and labor during the past 30 years, is highlighted. We isolate crucial collective political actors--industrial workers, students and intellectuals, business groups, technocrats, the military, the urban semiproletariat--and discuss their current and/or potential role in the struggle for democratization. The conclusion traces political changes through mid-1989, emphasizing the incomplete nature of the accomplished reforms and the potential complications that the reunification issue raises for further democratization. We conclude that the political reform movement faces a number of structural constraints generated by issues of international competitiveness and the configuration of interests in the domestic political economy. This suggests that, at best, South Korea is likely to end up with a "restricted" or "controlled" form of democracy. [ABSTRACT FROM AUTHOR]