We present QCA, a package for performing Qualitative Comparative Analysis (QCA). QCA is becoming increasingly popular with social scientists, but none of the existing software alternatives covers the full range of core procedures. This gap is now filled by QCA. After a mapping of the method’s diffusion, we introduce some of the package’s main capabilities, including the calibration of crisp and...

The notion of quantum-dot cellular automata (QCA) as a possible replacement paradigm for conventional transistor-based logic is reviewed. Experiments using metal tunnel structures demonstrating a functional QCA cell are presented. It is shown that single electron tunnelling transistors used as electrometers verify proper switching of the QCA cell. Additionally, we provide evidence for a QCA cel...

quantum dot cellular automata (qca) is one of the important nano-level technologies for implementation of both combinational and sequential systems. qca have the potential to achieve low power dissipation and operate high speed at thz frequencies. however large probability of occurrence fabrication defects in qca, is a fundamental challenge to use this emerging technology. because of these vari...

Optimizing arithmetic primitives such as quantum-dot cellular automata (QCA) adders is important for investigating high-performance QCA computers in this emerging nano-technological paradigm. In this paper, we demonstrate that QCA ripple carry adder and bit-serial adder designs actually outperform carry-look-ahead and carry-select adder designs because of the increase in required interconnects....

BACKGROUND Quantitative coronary angiography (QCA) has inherent limitations for displaying complex vascular anatomy, yet it remains the gold standard for stenosis quantification. OBJECTIVE To investigate the accuracy of stenosis assessment by multi-detector computed tomography (MDCT) and QCA compared to known dimensions. METHODS Nineteen acrylic coronary vessel phantoms with precisely drill...

Quantum-dot Cellular Automata (QCA) is a possible future nanoelectronic computing technology, based on cells of coupled quantum dots. The QCA cells have features on the very low nanometer scale, much smaller than the present state of art size of the smallest transistor. This paper presents design and layout of novel XOR gate implementations with minimum complexity and cell count in comparison w...

In the near future the era of Beyond CMOS will start as the scaling of the current CMOS technology will reach the fundamental limit. QCA (Quantum-dot Cellular Automata) is the transistor less computation paradigm and viable candidate for Beyond CMOS device technology. The complete state of art survey on QCA is presented in this paper. This paper addresses the QCA background, its possible implem...

Quantum-dot Cellular Automata (QCA) is a nanotechnology which has potential applications in future computers. In this paper, a method for reducing the number of majority gates (a QCA logic primitive) is developed to facilitate the conversion of SOP expressions of three-variable Boolean functions into QCA majority logic. Thirteen standard functions are proposed to represent all three-variable Bo...

BACKGROUND The relative merits of quantitative coronary analysis (QCA) and intravascular ultrasound (IVUS) for the assessment of progression/regression in coronary artery disease are uncertain. To explore this subject further, we analyzed the angiographic and IVUS data derived from a contemporary clinical trial population. METHODS AND RESULTS We investigated the relationships between QCA and ...

Physical limitations of Complementary Metal-Oxide-Semiconductors (CMOS) technology at nanoscale and high cost of lithography have provided the platform for creating Quantum-dot Cellular Automata (QCA)-based hardware. The QCA is a new technology that promises smaller, cheaper and faster electronic circuits, and has been regarded as an effective solution for scalability problems in CMOS technolog...