Fang Liu

A density-based approach for text extraction in images

In this paper we describe a new approach to distinguish and extract text from images with various objects and complex backgrounds. The goal of our approach is to present characters in images with clear background and without other objects. The proposed approach mainly includes two steps. Firstly, a density-based clustering method is employed to segment candidate characters by integrating spatial connectivity and color feature of characterspsila pixels. In most images, colors of pixels in one character are commonly non-uniform due to the noise. So a new histogram segmentation method is proposed in this step to obtain the color thresholds of characters. Secondly, priori knowledge and texture-based method are performed on the candidate characters to filter the non-characters. Experimental results show that the proposed approach has a good performance in character extraction rate.

Image Analysis of the Relationship between Changes of Cornea and Postmortem Interval

Opacity of the cornea is one of the important indices for estimating time of death. Now the work is done by forensic medical experts. An unbiased estimation method is needed. This paper proposed a method for finding the relationship between changes of cornea and postmortem intervals by processing and analyzing images. Firstly, a histogram based image segmentation method is proposed to extract corneal regions from pictures of rabbits eye. Secondly, texture and color features are used to describe the extracted corneal regions. Those features are carefully chosen to represent the changes of cornea in different postmortem intervals. A KNN classifier is used to reveal the association of image features and postmortem intervals. The experimental results show that cornea image features can be used to automatically estimate postmortem interval.

Adiabatically implementing quantum gates

We show that, through the approach of quantum adiabatic evolution, all of the usual quantum gates can be implemented efficiently, yielding running time of order O(1). This may be considered as a useful alternative to the standard quantum computing approach, which involves quantum gates transforming quantum states during the computing process.

Partial adiabatic quantum search algorithm and its extensions

In this paper, we again discuss quantum search by partial adiabatic evolution, which was first proposed by Zhang et al. In contrast to previous conclusions, we show that partial adiabatic search does not improve the time complexity of a local adiabatic algorithm. Firstly, we show a variant of this algorithm and find that it is equivalent to the original partial adiabatic algorithm, in the sense of the same time complexity. But we give two alternate viewpoints on this “new” adiabatic algorithm—“global” adiabatic evolution and local adiabatic evolution approaches, respectively. Then, we discuss how global and local adiabatic quantum search can be recast in the framework of partial adiabatic search algorithm. It is found here that the former two algorithms could be considered as special cases of the later one when appropriately tuning the evolution interval of it. Also this implies the flexibility of quantum search based on partial adiabatic evolution.

A systematic review of metabolomics biomarkers for Bisphenol A exposure

IntroductionBisphenol A (BPA), 2,2-bis(4-hydroxyphenyl) propane, a common industrial chemical which has extremely huge production worldwide, is ubiquitous in the environment. Human have high risk of exposing to BPA and the health problems caused by BPA exposure have aroused public concern. However, the biomarkers for BPA exposure are lacking. As a rapidly developing subject, metabolomics has accumulated a large amount of valuable data in various fields. The secondary application of published metabolomics data could be a very promising field for generating novel biomarkers whilst further understanding of toxicity mechanisms.ObjectivesTo summarize the published literature on the use of metabolomics as a tool to study BPA exposure and provide a systematic perspectives of current research on biomarkers screening of BPA exposure.MethodsWe conducted a systematic search of MEDLINE (PubMed) up to the end of June 25, 2017 with the key term combinations of ‘metabolomics’, ‘metabonomics’, ‘mass spectrometry’, ‘nuclear magnetic spectroscopy’, ‘metabolic profiling’ and ‘amino acid profile’ combined with ‘BPA exposure’. Additional articles were identified through searching the reference lists from included studies.ResultsThis systematic review included 15 articles. Intermediates of glycolysis, Krebs cycle, β oxidation of long chain fatty acids, pentose phosphate pathway, nucleoside metabolism, branched chain amino acid metabolism, aromatic amino acids metabolism, sulfur-containing amino acids metabolism were significantly changed after BPA exposure, suggesting BPA had a highly complex toxic effects on organism which was consistent with existing studies. The biomarkers most consistently associated with BPA exposure were lactate and choline.ConclusionExisting metabolomics studies of BPA exposure present heterogeneous findings regarding metabolite profile characteristics. We need more evidence from target metabolomics and epidemiological studies to further examine the reliability of these biomarkers which link to low, environmentally relevant, exposure of BPA in human body.

On the General Class of Models of Adiabatic Evolution

The general class of models of adiabatic evolution was proposed to speed up the usual adiabatic computation in the case of quantum search problem. It was shown [8] that, by temporarily increasing the ground state energy of a time-dependent Hamiltonian to a suitable quantity, the quantum computation can perform the calculation in time complexity O(1). But it is also known that if the overlap between the initial and final states of the system is zero, then the computation based on the generalized models of adiabatic evolution can break down completely. In this paper, we find another severe limitation for this class of adiabatic evolution-based algorithms, which should be taken into account in applications. That is, it is still possible that this kind of evolution designed to deal with the quantum search problem fails completely if the interpolating paths in the system Hamiltonian are chosen inappropriately, while the usual adiabatic evolutions can do the same job relatively effectively. This implies that it is not always recommendable to use nonlinear paths in adiabatic computation. On the contrary, the usual simple adiabatic evolution may be sufficient for effective use.

Generalized relation between fidelity and quantum adiabatic evolution

Wei et al. have shown an accurate relation between the running time and the distance of the initial state and the final state of a local adiabatic evolution, that is, the adiabatic running time can be completely determined by the distance between the states. They also asked whether more complicated adiabatic evolutions have similar simple relation. We show that the adiabatic evolution with a general class of models of interpolation path proposed by Das et al. is just such another kind of adiabatic evolution which enjoys the relation discussed by Wei et al.

A Modified Adiabatic Quantum Algorithm for Evaluation of Boolean Functions

In this paper, we propose a modified construction of the quantum adiabatic algorithm for Boolean functions studied by M. Andrecut et al. [13, 14]. Our algorithm has the time complexity O(1) for the evaluation of Boolean functions, without additional computational cost of implementing the driving Hamiltonian, which is required by the adiabatic evolution described in [13, 14].

Generalized quantum partial adiabatic evolution

Due to the intrinsic similarity between partial adiabatic evolution and global adiabatic evolution, we generalize the partial adiabatic evolution proposed recently to its local adiabatic algorithm version. However, unlike that the local adiabatic evolution can speed up the global adiabatic algorithm quadratically, we prove that this new quantum algorithm presented here just has the same time complexity as the original partial adiabatic evolution. This may imply the optimality of the original partial adiabatic evolution or its generalized version. Additionally, a concrete example is given to further support our conclusion.

An alternate quantum adiabatic evolution for the Deutsch---Jozsa problem

Deutsch–Jozsa algorithm has been implemented via quantum adiabatic evolutions by Das et al. (Phys Rev A 65:062310, 2002) and Wei et al. (Phys Lett A 354:271, 2006). In the latter literature, the authors have shown a modified version of the adiabatic evolution which can improve the performance of the algorithm of S. Das et al’s to constant time. In this paper, we also improve the algorithm of S. Das et al’s in a constant time but by using a different construction of adiabatic evolution, i.e., adding ancillary qubits. The algorithm in this paper provides an alternative option to potential users.