BACKGROUND Systematic reviews evaluating complex interventions often encounter substantial clinical heterogeneity in intervention components and implementation features making synthesis challenging. Qualitative comparative analysis (QCA) is a non-probabilistic method that uses mathematical set theory to study complex phenomena; it has been proposed as a potential method to complement traditiona...

In this paper, we discuss arithmetic structures based on quantum cellular automata (QCA). By taking advantage of the unique capabilities of QCA we are able to design interesting computational architectures. We describe important design considerations and show how addition and multiplication circuits can be implemented using QCADesigner, a QCA design tool which has been developed in our laborato...

Quantum dot Cellular Automata (QCA) technology is a possible CMOS substitute. It requires a clock-like signal to assure information propagation. This likens a QCA circuit to a fully pipelined architecture, where pipeline depth is layout dependent. Only asynchronous organization of architectural blocks enables the realization of complex circuits. The use of Null Convention Logic (NCL) is one amo...

Quantum-dot Cellular Automata (QCA) is an emerging and promising technology that provides significant improvements over CMOS. Recently QCA has been advocated as an applicant for implementing reversible circuits. However QCA, like other Nanotechnologies, suffers from a high fault rate. The main purpose of this paper is to develop a fault tolerant model of QCA circuits by redundancy in hardware a...

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...

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...

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 ...