arXiv subjects

Jinjin Zhang

Publications and source records attributed to Jinjin Zhang.

30 records · Page 2Linked to original sources

arXiv2019

A Feasible Framework for Arbitrary-Shaped Scene Text Recognition

Deep learning based methods have achieved surprising progress in Scene Text Recognition (STR), one of classic problems in computer vision. In this paper, we propose a feasible framework for multi-lingual arbitrary-shaped STR, including instance segmentation based text detection and language model based attention mechanism for text recognition. Our STR algorithm not only recognizes Latin and Non-Latin characters, but also supports arbitrary-shaped text recognition. Our method wins the championship on Scene Text Spotting Task (Latin Only, Latin and Chinese) of ICDAR2019 Robust Reading Challenge on ArbitraryShaped Text Competition. Code is available at https://github.com/zhang0jhon/AttentionOCR.

cs.CV↗

arXiv2018

Pose-Based Two-Stream Relational Networks for Action Recognition in Videos

Recently, pose-based action recognition has gained more and more attention due to the better performance compared with traditional appearance-based methods. However, there still exist two problems to be further solved. First, existing pose-based methods generally recognize human actions with captured 3D human poses which are very difficult to obtain in real scenarios. Second, few pose-based methods model the action-related objects in recognizing human-object interaction actions in which objects play an important role. To solve the problems above, we propose a pose-based two-stream relational network (PSRN) for action recognition. In PSRN, one stream models the temporal dynamics of the targeted 2D human pose sequences which are directly extracted from raw videos, and the other stream models the action-related objects from a randomly sampled video frame. Most importantly, instead of fusing two-streams in the class score layer as before, we propose a pose-object relational network to model the relationship between human poses and action-related objects. We evaluate the proposed PSRN on two challenging benchmarks, i.e., Sub-JHMDB and PennAction. Experimental results show that our PSRN obtains the state-the-of-art performance on Sub-JHMDB (80.2%) and PennAction (98.1%). Our work opens a new door to action recognition by combining 2D human pose extracted from raw video and image appearance.

cs.CV↗

arXiv2017

Anomalous behavior of membrane fluidity caused by copper-copper bond coupled phospholipids

Membrane fluidity, well-known to be essential for cell functions, is obviously affected by copper. However, the underlying mechanism is still far from being understood, especially on the atomic level. Here, we unexpectedly observed that a decrease in phospholipid (PL) bilayer fluidity caused by Cu2+ was much more significant than those induced by Zn2+ and Ca2+, while a comparable reduction occurred in the last two ions. This finding clearly disagrees with the placement in the periodic table of Cu just next to Zn and far from Ca. The physical nature was revealed to be a special attraction between Cu+ cations, which can induce a motif forming of two phospholipids coupled by Cu-Cu bond (PL-diCu-PL). Namely, upon Cu2+ ion binding to a negatively charged phosphate group of lipid, Cu2+ was reduced to Cu+. The special attraction of the cations then caused one Cu+ ion simultaneously binding to two lipids and another Cu+, resulting in the formation of PL-diCu-PL structure. In contrast, this attraction cannot occur in the cases of Zn and Ca ions due to their electron structure. Remarkably, besides lipids, the phosphate group widely exists in other biological molecules, including DNA, RNA, ADP and ATP, which would also induce the similar structure of Cu ions with the molecules. Our findings thus provide a new view for understanding the biological functions of copper and the mechanism underlying copper-related diseases.

physics.bio-ph↗

arXiv2015

On the greatest solution of equations in $\text{CLL}_R$

It is shown that, for any equation $X=_{RS} t_X$ in the LLTS-oriented process calculus $\text{CLL}_R$, if $X$ is strongly guarded in $t_X$, then the recursive term $\langle X|X=t_X \rangle$ is the greatest solution of this equation w.r.t Lüttgen and Vogler's ready simulation.

cs.LO↗

arXiv2015

Axiomatizing Lüttgen and Vogler's ready simulation for finite processes in $\text{CLL}_R$

In the framework of logic labelled transition system, a variant of weak ready simulation has been presented by Lüttgen and Vogler. It has been shown that such behavioural preorder is the largest precongruence w.r.t parallel and conjunction composition satisfying desired properties. This paper offers a ground-complete axiomatization for this precongruence over processes containing no recursion in the calculus $\text{CLL}_R$. Compared with usual inference system for process calculus, in addition to axioms about process operators, such system contains a number of axioms to characterize the interaction between process operators and logical operators.

cs.LO↗

arXiv2014

Greatest solutions of equations in $\text{CLL}_R$ and its application

This paper explores the process calculus $\text{CLL}_R$ furtherly. First, we prove that for any equation $X=_{RS} t_X$ such that $X$ is strongly guarded in $t_X$, $\langle X|X=t_X \rangle$ is the largest solution w.r.t $\sqsubseteq_{RS}$. Second, we encode a fragment of action-based CTL in $\text{CLL}_R$.

cs.LO↗

arXiv2013

On Recursive Operations Over Logic LTS

Recently, in order to mix algebraic and logic styles of specification in a uniform framework, the notion of a logic labelled transition system (Logic LTS or LLTS for short) has been introduced and explored. A variety of constructors over LLTS, including usual process-algebraic operators, logic connectives (conjunction and disjunction) and standard temporal operators (always and unless), have been given. However, no attempt has made so far to develop general theory concerning (nested) recursive operations over LLTSs and a few fundamental problems are still open. This paper intends to study this issue in pure process-algebraic style. A few fundamental properties, including precongruence and the uniqueness of consistent solutions for equations, will be established.

cs.LO↗

arXiv2012

Merging Process Algebra and Action-based Computation Tree Logic

Process algebra and temporal logic are two popular paradigms for the specification, verification and systematic development of reactive and concurrent systems. These two approaches take different standpoint for looking at specifications and verifications, and offer complementary advantages. In order to mix algebraic and logic styles of specification in a uniform framework, the notion of a logic labelled transition system (LLTS) has been presented and explored by Luttgen and Vogler. This paper intends to propose a LLTS-oriented process calculus which, in addition to usual process-algebraic operators, involves logic connectives (conjunction and disjunction) and standard temporal operators (always and unless). This calculus preserves usual properties of these logic operators, allows one to freely mix operational and logic operators, and supports compositional reasoning. Moreover, the links between this calculus and Action-based Computation Tree Logic (ACTL) including characteristic formulae of process terms, characteristic processes of ACTL formulae and Galois connection are explored.

cs.LO↗

arXiv2012

A control strategy algorithm for finite alternating transition systems

Recently, there has been an increasing interest in the formal analysis and design of control systems. In this area, in order to reduce the complexity and scale of control systems, finite abstractions of control systems are introduced and explored. Amongst, Pola and Tabuada construct finite alternating transition systems as approximate finite abstractions for control systems with disturbance inputs [SIAM Journal on Control and Optimization, Vol. 48, 2009, 719-733]. Given linear temporal logical formulas as specifications, this paper provides a control strategy algorithm to find control strategies of Pola and Tabuada's abstractions enforcing specifications.

math.OC↗

arXiv2012

Linear time logic control of linear systems with disturbances

The formal analysis and design of control systems is one of recent trends in control theory. In this area, in order to reduce the complexity and scale of control systems, finite abstractions of control systems are introduced and explored. In non-disturbance case, the controller of control systems is often generated from the controller of finite abstractions. Recently, Pola and Tabuada provide approximate finite abstractions for linear control systems with disturbance inputs. However, these finite abstractions and original linear systems do not always share the identical specifications, which obstructs designing controller (of linear systems) based on their finite abstractions. This paper tries to bridge such gap between linear systems and their finite abstractions.

math.OC↗

arXiv2012

A Modal Characterization of Alternating Approximate Bisimilarity

Recently, alternating transition systems are adopted to describe control systems with disturbances and their finite abstract systems. In order to capture the equivalence relation between these systems, a notion of alternating approximate bisimilarity is introduced. This paper aims to establish a modal characterization for alternating approximate bisimilarity. Moreover, based on this result, we provide a link between specifications satisfied by the samples of control systems with disturbances and their finite abstractions.

cs.LO↗

arXiv2012

A Process Calculus with Logical Operators

In order to combine operational and logical styles of specifications in one unified framework, the notion of logic labelled transition systems (Logic LTS, for short) has been presented and explored by Lüttgen and Vogler in [TCS 373(1-2):19-40; Inform. & Comput. 208:845-867]. In contrast with usual LTS, two logical constructors $\wedge$ and $\vee$ over Logic LTSs are introduced to describe logical combinations of specifications. Hitherto such framework has been dealt with in considerable depth, however, process algebraic style way has not yet been involved and the axiomatization of constructors over Logic LTSs is absent. This paper tries to develop Lüttgen and Vogler's work along this direction. We will present a process calculus for Logic LTSs (CLL, for short). The language CLL is explored in detail from two different but equivalent views. Based on behavioral view, the notion of ready simulation is adopted to formalize the refinement relation, and the behavioral theory is developed. Based on proof-theoretic view, a sound and ground-complete axiomatic system for CLL is provided, which captures operators in CLL through (in)equational laws.

cs.LO↗