bluuebunny/crossref_metadata_2025 huggingface dataset:
A Memetic Particle Swarm Optimization Algorithm for Community Detection in Complex Networks
Authors: Zhang Cheng , Hei Xinhong , Yang Dongdong , Wang Lei
Published: October 2015

In recent years, community detection has become a hot research topic in complex networks. Many of the proposed algorithms are for detecting community based on the modularity Q. However, there is a resolution limit problem in modularity optimization methods. In order to detect the community structure more effectively, a memetic particle swarm optimization algorithm (MPSOA) is proposed to optimize the modularity density by introducing particle swarm optimization-based global search operator and tabu local search operator, which is useful to keep a balance between diversity and convergence. For comparison purposes, two state-of-the-art algorithms, namely, meme-net and fast modularity, are carried on the synthetic networks and other four real-world network problems. The obtained experiment results show that the proposed MPSOA is an efficient heuristic approach for the community detection problems.
A Dynamic Local Path Planning Method for Outdoor Robot Based on Characteristics Extraction of Laser Rangefinder and Extended Support Vector Machine
Authors: Yu Lingli , Zhou Kaijun
Published: October 2015

For dynamic path planning problem under unstructured environment, firstly, successive edge following and least squares method (SEF-LSM) is adopted to extract environment characteristics of laser rangefinder data, and SEF-LSM with logical reasoning (SEF-LSM-LR) is proposed for dynamic obstacles characteristics detection. Furthermore, the perpendicularity (PERP) algorithm is utilized to identify dynamic vehicle, according to the perpendicularity attribute of vehicle. Secondly, all the laser rangefinder scanning points are marked as negative ([Formula: see text]) or positive ([Formula: see text]1), and the scanning points of one dynamic obstacle are marked as the same label. Thirdly, extended support vector machine (ESVM) is designed for outdoor robot local path planning under unstructured environment, which consider the practical start-goal position and heading constraints, robot kinematic constraint, and curvature constraint, moreover, the emergency obstacle is regarded as disturbances during planning processing. Finally, the optimal path is chosen by the shortest distance evaluation function. Lots of outdoor simulations show that the proposed method solve the dynamic planning problem under unstructured environment, and their effectiveness performance are verified for outdoor robot path planning.
An Adaptive Niching-Based Evolutionary Algorithm for Optimizing Multi-Modal Function
Authors: Luo Jie , Gu Fangqing
Published: October 2015

This paper presents a niching-based evolutionary algorithm for optimizing multi-modal optimization function. Provided that the potential optima are characterized by a relatively smaller objective value than their neighbors and by a relatively large distance from points with smaller objective values, we identify potential optima from individuals. Using them as seeds, a population is decomposed into a number of subpopulations without introducing new parameters. Moreover, we present an adaptive allocating strategy of assigning different computational resources to different subpopulations upon the fact that discovering different optima may have different computational difficulty. The proposed method is compared with three state-of-the-art multi-modal optimization approaches on a benchmark function set. The extensive experimental results demonstrate its efficacy.
Investigation of Intermittent Resistive Faults in Digital CMOS Circuits
Authors: Kerkhoff Hans G. , Ebrahimi Hassan
Published: October 2015

No fault found (NFF) is a major threat in extremely dependable high-end process node integrated systems, in e.g., avionics. One category of NFFs is the intermittent resistive fault (IRF), often originating from bad (e.g., via- or TSV-based) interconnections. This paper will show the impact of these faults on the behavior of a digital CMOS circuit via simulation. As the occurrence rate of this kind of defects can take e.g., one month, while the duration of the defect can be as short as 50[Formula: see text]ns, thus to evoke and detect these faults is a huge scientific challenge. Two methods to detect short pulses induced by IRFs are proposed. To improve the task of maintenance of avionics and reduce the current high debugging costs, an on-chip data logging system with time stamp and stored environmental conditions is introduced. Finally, a hardware implementation of an IRF generator is presented.
A zero polynomial of virtual knots
Authors: Jeong Myeong-Ju
Published: October 2015

In 2013, Cheng and Gao introduced the writhe polynomial of virtual knots and Kauffman introduced the affine index polynomial of virtual knots. We introduce a zero polynomial of virtual knots of a similar type by considering weights of a suitable collection of crossings of a virtual knot diagram. We show that the zero polynomial gives a Vassiliev invariant of degree 1. It distinguishes a pair of virtual knots that cannot be distinguished by the affine index polynomial and the writhe polynomial.
Thermodynamic behavior and stability of Polytropic gas
Authors: Moradpour H. , Abri A. , Ebadi H.
Published: October 2015

We focus on the thermodynamic behavior of Polytropic gas as a candidate for dark energy (DE). We use the general arguments of thermodynamics to investigate its properties and behavior. We find that a Polytropic gas can exhibit the DE-like behavior. It also may be used to simulate a fluid with zero pressure at the small volume and high temperature limits. Briefly, our study shows that this gas may be used to describe the universe expansion history from the matter dominated era to the current accelerating era. By applying some initial conditions to the system, we can establish a relation between the Polytropic gas parameters and the initial conditions. Relationships with related works have also been addressed.
Advances in Mechanics of Soft Materials: A Review of Large Deformation Behavior of Hydrogels
Authors: Liu Zishun , Toh William , Ng Teng Yong
Published: October 2015

Hydrogels possess magnificent properties which may be harnessed for novel applications. However, this is not achievable if the mechanical behaviors of hydrogels are not well understood. This paper aims to provide the reader with a bird's eye view of the mechanics of hydrogels, in particular the theories associated with deformation of hydrogels, the phenomena that are commonly observed, and recent developments in applications of hydrogels. Besides theoretical analyses and experimental observations, another feature of this paper is to provide an overview of how mechanics can be applied.
On the minimal distance between elliptic fixed points for geometrically finite Fuchsian groups
Authors: Friedman Joshua S.
Published: October 2015

Let [Formula: see text] be a geometrically finite Fuchsian group acting on the upper half-plane [Formula: see text]. Let [Formula: see text] denote the set of elliptic fixed points of [Formula: see text] in [Formula: see text]. We give a lower bound on the minimal hyperbolic distance between points in [Formula: see text]. Our bound depends on a universal constant and the length of the smallest closed geodesic on [Formula: see text].
On the mean square of an arithmetical error term of the Selberg class in short intervals
Authors: Cao Xiaodong , Tanigawa Yoshio , Zhai Wenguang
Published: October 2015

Let [Formula: see text] be a Dirichlet series in the Selberg class of degree [Formula: see text] and let [Formula: see text] be the arithmetical error term of [Formula: see text]. We derive two kinds of the mean square estimates of [Formula: see text] in short intervals of Jutila’s type. Our method is based on the truncated Tong-type formula of [Formula: see text]. We also give several applications of these estimates in the arithmetical problems.
Unitary completions of locally algebraic and locally analytic principal series of p-adic GL2
Authors: Kidwell Keenan
Published: October 2015

We generalize a result of Emerton on the relationship between unitary completions of locally [Formula: see text]-analytic and locally [Formula: see text]-algebraic principal series representations induced from certain locally [Formula: see text]-algebraic characters of the diagonal torus of [Formula: see text], where [Formula: see text] is a finite extension of [Formula: see text]. Namely, under a non-critical slope hypothesis on the character being induced, the map on universal unitary completions arising from the inclusion of the locally algebraic induction into the locally analytic induction is a topological isomorphism. (Emerton proved this result for [Formula: see text].) The main ingredients in carrying out a “several-variable” version of Emerton’s argument are the description of the local convex space of locally [Formula: see text]-analytic functions on the group [Formula: see text] in terms of the embeddings of [Formula: see text] into our [Formula: see text]-adic coefficient field, and a generalization by Breuil of the classical result of Amice-Vélu and Vishik on “tempered distributions” on [Formula: see text].
Seismic Fragility Assessment of Skewed MSSS-I Girder Concrete Bridges with Unequal Height Columns
Authors: Noori Hamed Zamani , Amiri Gholamreza Ghodrati , Nekooei Masoud , Zakeri Behzad
Published: October 2015

Multi Span Simply Supported Bridges (MSSS) are categorized among the most vulnerable bridge classes and their vulnerability increases when different sources of irregularities such as skewness as well as columns height differences are included. Different sources of irregularities make the irregular bridge more complicated in case of dynamic response than regular bridges, and therefore a comprehensive study should be implemented to explore the effect of different irregularities on seismic performance of bridges individually and jointly. This paper explores the effect of skewness and unequal height columns on the seismic response of MSSS-I girder concrete bridges commonly constructed in Central and Southeastern United States (CSUS). The scope of the study is limited to tree spans which are the most prevalent spans in this class of bridges. The results show that the component fragilities become more sensitive to column height ratio with increase in the bridge skew angle particularly in longitudinal direction. The study of the combined effects of skewness and column height ratio on the bridge system fragility also reveals that the column height ratio has negative effect on the fragility of bridge system in all damage states and different skew angles but this effect increases by increasing the skewness as well as damage state of interest.
Synthesis and photocatalytic activities of Nd-doped TiO2 mesoporous microspheres
Authors: Liu Xijian , Sun Yangang , Wang Yeying , Zhang Lijuan , Lu Jie
Published: October 2015

Nd-doped TiO2 mesoporous microspheres with possessing regular micro/nanostructure were synthesized by a simple and facile method. The structure and optical properties of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption–desorption isotherms and UV-Visible absorbance spectroscopy. It was revealed that Nd-doped TiO2 mesoporous microspheres are composed of primary nanoparticles with a particle size of [Formula: see text]25[Formula: see text]nm. The photocatalytic activities of all the samples were evaluated by degradation methyl orange (MO) in aqueous solution as a model reaction under xenon lamp light irradiation. The results showed that the doped samples demonstrated a higher photocatalytic activity than TiO2 mesoporous microspheres, and the MO of 10[Formula: see text]mg/mL almost could be completely degraded by the Nd-doped TiO2 mesoporous sample (the dosage of Nd salt to TiO2 is 6%) under xenon lamp light irradiation within 1[Formula: see text]h.
A Novel Cooperative ARQ Method for Wireless Sensor Networks
Authors: Wang Haiyong , Yang Geng , Gu Yiran , Xu Jian , Sun Zhixin
Published: October 2015

In wireless sensor networks, cooperative communication can combat the effects of channel fading by exploiting diversity gain achieved via cooperation communication among the relay nodes. A cooperative automatic retransmission request (ARQ) protocol based on two-relay node selection was proposed in this paper. A novel discrete time Markov chain model in order to analyze the throughput and energy efficiency was built, and system throughput and energy efficiency performance of proposed protocol and traditional ARQ protocol were studied based on such model. The numerical results reveal that the throughput and energy efficiency of the proposed protocol could perform better when compared with the traditional ARQ protocol.
Listeria monocytogenesMeningitis in an Immunosuppressed Patient with Autoimmune Hepatitis and IgG4 Subclass Deficiency
Authors: Gaini Shahin
Published: October 2015

A 51-year-old Caucasian woman withListeria monocytogenesmeningitis was treated and discharged after an uncomplicated course. Her medical history included immunosuppressive treatment with prednisolone and azathioprine for autoimmune hepatitis. A diagnostic work-up after the meningitis episode revealed that she had low levels of the IgG4 subclass. To our knowledge, this is the first case report describing a possible association between autoimmune hepatitis and the occurrence ofListeria monocytogenesmeningitis, describing a possible association betweenListeria monocytogenesmeningitis and deficiency of the IgG4 subclass and finally describing a possible association betweenListeria monocytogenesmeningitis and immunosuppressive therapy with prednisolone and azathioprine.
Diagnosis of Roller Bearings Compound Fault Using Underdetermined Blind Source Separation Algorithm Based on Null-Space Pursuit
Authors: Cui Lingli , Wu Chunguang , Ma Chunqing , Wang Huaqing
Published: October 2015

In order to solve the problem of underdetermined blind source separation (BSS) in the diagnosis of compound fault of roller bearings, an underdetermined BSS algorithm based on null-space pursuit (NSP) was proposed. In this algorithm, the signal model of faulty roller bearing is firstly used to construct an appropriate differential operator in null space. With the constructed differential operator, the mixed signals collected by the vibration sensor are decomposed into a series of stacks of narrow band signal containing the characteristics of faulty bearing. Finally, the underdetermined problem is transformed to an overdetermined problem by combining the narrow band signals and the original mixed signals into a new group of observed signals. In this way, the separation of the mixed signals can be realized. Experiments and engineering data analyses show that the problem of underdetermined BSS can be solved effectively by this approach, and then the compound fault of the roller bearing can be separated.
Synthesis, Structural and Optical Properties of TOPO and HDA Capped Cadmium Sulphide Nanocrystals, and the Effect of Capping Ligand Concentration
Authors: Onwudiwe Damian C. , Hrubaru Madalina , Ebenso Eno E.
Published: October 2015

The thermal decomposition of bis(N,N‐diallyldithiocarbamato)Cd(II) in a “one‐pot” synthesis in tri‐n‐octylphosphine oxide (TOPO) and hexadecylamine (HDA) afforded CdS (TOPO‐CdS and HDA‐CdS) of varying optical properties and morphologies. The influence of the ratio of the precursor concentration to the capping molecule, as a factor affecting the morphology and size of the nanoparticles, was investigated. The particles varied in shape from spheres to rods and show quantum size effects in their optical spectra with clear differences in the photoluminescence (PL) spectra. The PL spectrum of the HDA capped CdS nanoparticles has an emission maximum centred at 468, 472, and 484 nm for the precursor to HDA concentration ratio of 1 : 10, 1 : 15, and 1 : 20, respectively, while the TOPO capped nanoparticles show emission peaks at 483, 494, and 498 nm at the same concentration ratio. Powdered X‐ray diffraction (p‐XRD) shows the nanoparticles to be hexagonal. The crystallinity of the nanoparticles was evident from high resolution transmission electron microscopy (HRTEM) which gave well‐defined images of particles with clear lattice fringes.
Further Results on Stability Analysis for Markovian Jump Systems with Time-Varying Delays
Authors: Kwon O. M. , Sakthivel R. , Park M. J.
Published: October 2015

This paper is concerned with the problem of stability analysis for Markovian jump systems with time-varying delays. By constructing a newly augmented Lyapunov-Krasovskii functional and combining Wirtinger-based integral inequality, an improved delay-dependent stability criterion within the framework of linear matrix inequalities (LMIs) is introduced. Based on the result of delay-dependent stability criterion, when linear systems have fast time-varying delays, a corresponding stability condition is given. Via three numerical examples, the improvements of the proposed criteria are shown by comparing maximum delay bounds provided by our theorems with the recent results.
Identification and Analysis of the SET-Domain Family in Silkworm,Bombyx mori
Authors: Zhao Hailong , Zheng Chunqin , Cui Hongjuan
Published: October 2015

As an important economic insect,Bombyx moriis also a useful model organism for lepidopteran insect. SET-domain-containing proteins belong to a group of enzymes named after a common domain that utilizes the cofactor S-adenosyl-L-methionine (SAM) to achieve methylation of its substrates. Many SET-domain-containing proteins have been shown to display catalytic activity towards particular lysine residues on histones, but emerging evidence also indicates that various nonhistone proteins are specifically targeted by this clade of enzymes. To explore their diverse functions of SET-domain superfamily in insect, we identified, cloned, and analyzed the SET-domains proteins in silkworm,Bombyx mori. Firstly, 24 genes containing SET domain from silkworm genome were characterized and 17 of them belonged to six subfamilies of SUV39, SET1, SET2, SUV4-20, EZ, and SMYD. Secondly, SET domains of silkworm SET-domain family were intraspecifically and interspecifically conserved, especially for the catalytic core “NHSC” motif, substrate binding site, and catalytic site in the SET domain. Lastly, further analyses indicated that silkworm SET-domain gene BmSu(var)3-9 owned different characterization and expression profiles compared to other invertebrates. Overall, our results provide a new insight into the functional and evolutionary features of SET-domain family.
Lithium-Ion Battery Cell-Balancing Algorithm for Battery Management System Based on Real-Time Outlier Detection
Authors: Piao Changhao , Wang Zhaoguang , Cao Ju , Zhang Wei , Lu Sheng
Published: October 2015

A novel cell-balancing algorithm which was used for cell balancing of battery management system (BMS) was proposed in this paper. Cell balancing algorithm is a key technology for lithium-ion battery pack in the electric vehicle field. The distance-based outlier detection algorithm adopted two characteristic parameters (voltage and state of charge) to calculate each cell’s abnormal value and then identified the unbalanced cells. The abnormal and normal type of battery cells were acquired by online clustering strategy and bleeding circuits (R= 33 ohm) were used to balance the abnormal cells. The simulation results showed that with the proposed balancing algorithm, the usable capacity of the battery pack increased by 0.614 Ah (9.5%) compared to that without balancing.
Different Persistence of the Cellular Effects Promoted by Protein Kinase CK2 Inhibitors CX-4945 and TDB
Authors: Girardi Cristina , Ottaviani Daniele , Pinna Lorenzo A. , Ruzzene Maria
Published: October 2015

We compare the cellular efficacy of two selective and cell permeable inhibitors of the antiapoptotic kinase CK2. One inhibitor, CX-4945, is already in clinical trials as antitumor drug, while the other, TDB, has been recently successfully employed to demonstrate the implication of CK2 in cellular (dis)regulation. We found that, upon treatment of cancer cells with these compounds, the extent of inhibition of endocellular CK2 is initially comparable but becomes significantly different after the inhibitors are removed from the cellular medium: while in CX-4945 treated cells CK2 activity is restored to control level after 24 h, in the case of TDB it is still strongly reduced after 4 days from removal. The biological effects of the two inhibitors have been analyzed by performing clonogenic, spheroid formation, and wound-healing assays: we observed a permanent inhibition of cell survival and migration in TDB-treated cells even after the inhibitor removal, while in the case of CX-4945 only its maintenance for the whole duration of the assay insured a persisting effect. We suggest that the superiority of TDB in maintaining kinase activity inhibited and perpetuating the consequent effects is an added value to be considered when planning new therapies based on CK2 targeting.
Approximate Image Reconstruction in Landscape Reflection Imaging
Authors: Régnier Rémi , Rigaud Gaël , Nguyen Maï K.
Published: October 2015

Simple reflection imaging of landscape (scenery or extended objects) poses the inverse problem of reconstructing the landscape reflectivity function from its integrals on some particular family of spheres. Such data acquisition is encoded in the framework of a Radon transform on this family of spheres. In spite of the existence of an exact inversion formula, the numerical landscape reflectivity function reconstitution is best obtained with an approximate but judiciously chosen reconstruction kernel. We describe the working of this reflection imaging modality and its theoretical handling, introduce an efficient and stable image reconstruction algorithm, and present simulation results to prove the validity of this choice as well as to demonstrate the feasibility of this imaging process.
Preparation of Mixed Semiconductors for Methyl Orange Degradation
Authors: Adhikari Sangeeta , Sarkar Debasish
Published: October 2015

Attempts were made to compare the photocatalytic efficacy in between quasi‐fiber and near spherical commercial grade ZnO through the addition of monoclinic WO3 nanocuboid. Mixed oxide semiconductors were assessed for their dye degradation performance under irradiation of visible light energy. Surface area and the particle morphology pattern have an influence on the resultant photocatalytic features of these mixed oxide composites. The high porous quasi‐fibrous ZnO was successfully fabricated by a simple solution combustion method. It is deliberately made of clusters of primary near spherical particles that supports WO3 nanocuboid embedment and shows interactive characteristics in comparison to the counterpart commercial near spherical ZnO combined with WO3. The photocatalytic activity significantly increases up to 95% under visible radiation for 90 min due to high surface area imparted by unique quasi‐fiber morphology. The photogenerated electron‐hole pair interaction mechanism has been proposed to support the photocatalytic behavior.
MR*-Tree: Novel Indexing and Retrieving Mechanism for Spatial Objects in Mobile PowerPoint Pages
Authors: Xiang Jianming , Zhou ZhangBing , Shu Lei , Liu Cong , Wang Qun
Published: October 2015

Different from the traditional office software, due to the limited storage and computational capability of mobile devices, how to support the page editing in a fast and energy-efficient manner is fundamental. To address this challenge, we propose an MR*-tree based indexing mechanism for supporting the fast and energy-efficient retrieval of spatial objects in mobile PowerPoint pages. Based on this, techniques are developed to support the operations when editing mobile PowerPoint pages. Prototype has been implemented for facilitating the operations of spatial objects when editing mobile PowerPoint pages. Experimental evaluations on computers, pads, and smart phones show the effectiveness and efficiency of this technique.
Atrial Fibrillation and Coronary Artery Disease as Risk Factors of Retinal Artery Occlusion: A Nationwide Population-Based Study
Authors: Yen Ju-Chuan , Lin Hsiu-Li , Hsu Chia-An , Li Yu-Chuan (Jack) , Hsu Min-Huei
Published: October 2015

We use Taiwanese national health insurance research database (NHIRD) to investigate whether thrombolism (carotid artery disease (CAD) as a surrogate) or embolism (atrial fibrillation (AF) as a surrogate) plays roles in later retinal artery occlusion (RAO) development and examine their relative weights. The relative risks of RAO between AF and CAD patients and controls were compared by estimating the crude hazard ratio with logistic regression. Kaplan-Meier analysis was used to calculate the cumulative incidence rates of developing RAO, and a log-rank test was used to analyze the differences between the survival curves. Separate Cox proportional hazard regressions were done to compute the RAO-free rate after adjusting for possible confounding factors such as age and sex. The crude hazard ratios were 7.98 for the AF group and 5.27 for the CAD group, and the adjusted hazard ratios were 8.32 and 5.34 for the AF and CAD groups, respectively. The observation time with RAO-free was shorter for AF compared with CAD group (1490 versus 1819 days). AF and CAD were both risk factors for RAO with different hazard ratios. To tackle both AF and CAD is crucial for curbing RAO.
A Mathematical Algorithm of Locomotive Source Localization Based on Hyperbolic Technique
Authors: Kabir Homayun , Kanesan Jeevan , Reza Ahmed Wasif , Ramiah Harikrishnan
Published: October 2015

Recent trend shows that sensors situated on an axis in two-dimensional scenario measuring the time difference of arrival (TDOA) and frequency difference of arrival (FDOA) of the emitting signal from a moving source can estimate the emitting signal’s position and velocity from the intersection point of hyperbola, which derives from TDOA and FDOA. However, estimating the location of an emitter based on hyperbolic measurements is a highly nonlinear problem with inconsistent data, which are created due to the measurement noise, the deviation between assumption model and actual field of the velocity, and so forth. In addition, the coefficient matrix of TDOA and FDOA equations set is singular in the linear sensor array network (LSAN). In this paper, a noniterative and simpler method is proposed to locate the instantaneous position of the moving source in LSAN by estimating the position and velocity based on TDOA and FDOA which does not have the convergence problem. In addition, the method avoids the singularity problem of LSAN by introducing the nuisance variables. The proposed method achieved the theoretical lower bound for near to far field with same and different velocity and different baseline of sensors in low to moderate noise.
Influence of Incorporation of Natural Fibers on the Physical, Mechanical, and Thermal Properties of Composites LDPE-Al Reinforced with Fique Fibers
Authors: Hidalgo-Salazar Miguel A. , Muñoz Mario F. , Mina José H.
Published: October 2015

This study shows the effect of the incorporation of natural fique fibers in a matrix formed by low-density polyethylene and aluminum (LDPE-Al) obtained in the recycling process of long-life Tetra Pak packaging. The reinforcement content was 10, 20, and 30% fibers, manufactured by hot-press compression molding of composite boards (LDPE-Al/fique). From the thermogravimetric analysis (TGA) it was determined that the proportions of the LDPE-Al were 75 : 25 w/w. Likewise, it was found that the aluminum particles increased the rigidity of the LDPE-Al, reducing the impact strength compared to LDPE recycled from Tetra Pak without aluminum; besides this, the crystallinity in the LDPE-Al increased with the presence of aluminum, which was observed by differential scanning calorimetry (DSC). The maximum strength and Young’s modulus to tensile and flexural properties increased with the incorporation of the fibers, this increase being a direct function of the amount of reinforcement contained in the material. Finally, a reduction in the density of the compound by the generation of voids at the interface between the LDPE-Al and fique fibers was identified, and there was also a greater water absorption due to weak interphase fiber-matrix and the hydrophilic fibers contained in the material.
Graph-Theoretic Based Connectivity Restoration Algorithms for Mobile Sensor Networks
Authors: Mi Zhenqiang , Hsiao Rong-Shue , Xiong Zenggang , Yang Yang
Published: October 2015

In mobile sensor networks (MSN), actuated sensors collaborate with each other in some predefined missions. The collaboration requires application-level coordination based on a strongly connected underlying network, which is often in an infrastructure-free ad hoc manner. The particular network topology provides flexibility as well as vulnerability to the potential applications of MSN; for example, the connectivity can be easily jeopardized if the network is partitioned into disjoint segments from the failure of some critical sensors. In this paper, a critical sensor determination and substitution (CSDS) strategy is proposed to address the important problem of network partitions in mobile sensor networks (MSN) due to the failure of particular sensors. CSDS utilizes a graph-theoretic method to locally identify critical sensors with 2-hop neighboring information. Then, an efficient backup sensor selection algorithm is proposed to monitor the critical sensors and, if necessary, substitute it in order to eliminate the partitions in MSN. The main contribution of our proposed work is that CSDS requires the relocation of only one sensor in each partition elimination process, so that the impacts on the primary missions of the MSN are minimized. Experimental simulations are conducted to evaluate the correctness and effectiveness of CSDS.
Data Uploading and Exchange Algorithm for Mobile Sensor Networks in the City Traffic Environment
Authors: Ren Tiaojuan , Chen Yourong , Zhou Binbin , Lv Hexin , Wang Zhangquan , Xu Sen , Yu Lizhe , Hong Zhen
Published: October 2015

Mobile sensor networks (MSN) in the city environment have dynamic topology and large amounts of data. In order to overcome the problem of data uploading and exchange, data uploading and exchange algorithm (DUEA) is proposed. In DUEA, the three-tier network architecture composed of vehicle nodes, relay nodes and sink nodes is considered. The link estimator, routing engine, and forwarding engine are modified based on CTP (collection tree protocol). In the link estimator, beacon packet is simplified. In the routing engine, the numbers of elements in the send queue of neighbor nodes, and link quality are weighed. The new calculation formulae of ETX value and selection method of father node are proposed. In the forwarding engine, different snooping methods are used for two types of data named general data and warning data. Simulation results show that compared with CTP, DUEA increases data throughput and transmission rate and reduces energy consumption of packet transmission when data is uploaded. DUEA also reduces average transmission delay when data is exchanged. Physical test results show that DUEA achieves desired effect in the testbed. DUEA is effective and feasible and outperforms CTP in the city traffic environment.
Leadership Style: School Perspective in Cameroon
Authors: Wirba Asan Vernyuy
Published: October 2015

This paper examines leadership styles of secondary school principals in Cameroon, in terms of transformational, transactional, and laissez-faire leadership styles. This paper discusses the leadership styles in Cameroon and puts forward ideas for continuous improvement. A qualitative approach, using a semistructured interview, was adopted. It was conducted on ten principals, ten teachers, and ten students. Majority of respondents from schools described their principals as transformational leaders. Doubts are cast on the nature of transformational leadership in schools in Cameroon, since there is less training and development for leadership in schools.
Effect of Interfacial Debonding on the Strength of Composite Structure-Similarity Scale Model for the Wing-Box
Authors: Sun Shiyong , Yang Rui , Yan Zibin , Qian Wei
Published: October 2015

Based on the wing-box structure, a model was established to analyze the strength of the scale model for the composite wing. Firstly, different failure criteria were set to determine damage onset of the components. The continuum damage variables were adopted in the stiffness degradation rule. Secondly, the interface elements were placed along the interface between the beam flange and the skin to investigate the effects of bonding strength on the ultimate load-carrying capacity of the wing-box. The failure modes of the wing-box structure were studied by using the nonlinear finite element method. The effect of flange’s width on the strength of wing-box was discussed based on the prediction method. The results indicated that the ultimate load-carrying capacity varied distinctly with the change of flange’s width. However, the bonding strength had limited effect on the model strength as the flange’s width increases to the critical value. The research methods and results of the study can serve as reference for the strength analysis on the scale model of composite wing as well as the determination of principles adopted in the design of the scale model for wing spar.
An Efficient Algorithm of Constructing Virtual Backbone Scheduling for Maximizing the Lifetime of Dual-Radio Wireless Sensor Networks
Authors: Liu Bing-Hong , Pham Van-Trung , Nguyen Ngoc-Tu
Published: October 2015

Wireless sensor networks have often been used to monitor environmental conditions, such as temperature, sound, and pressure. Because the sensors are expected to work on batteries for a long time without charging their batteries, the major challenge in the design of wireless sensor networks is to enhance the network lifetime. Recently, many researchers have studied the problem of constructing virtual backbones, which are backbones used for different time periods, to prolong the network lifetime. In this paper, we study the problem of constructing virtual backbones in dual-radio wireless sensor networks to maximize the network lifetime, called the Maximum Lifetime Backbone Scheduling for Dual-Radio Wireless Sensor Network problem, where each sensor is equipped with two radio interfaces. The problem is shown to be NP-complete here. In addition, rather than proposing a centralized algorithm, a distributed algorithm, called a Dominating-Set-Based Algorithm (DSBA), is proposed for a wide range of wireless sensor networks to find a backbone when a new one is required. Simulation results show that the proposed algorithm outperforms some existing algorithms.
A Hybrid MMC Topology with dc Fault Ride-Through Capability for MTDC Transmission System
Authors: Meng Xinhan , Li Ke-Jun , Wang Zhuodi , Yan Wenning , Zhao Jianguo
Published: October 2015

This paper proposes a hybrid modular multilevel converter (MMC) topology based on mismatched-cascade mechanism. The blocking conditions of different submodule (SM) structures under dc fault are analyzed and a series double submodule is presented. With series-double submodules and mismatched-cascade submodules, the proposed hybrid MMC can ride-through the dc side short-circuit fault and provide an output voltage with the feature of low harmonic content. This hybrid MMC topology can be used in the VSC based multiterminal dc (VSC-MTDC) transmission system. The dc fault ride-through properties of the new structure and the total harmonic distortion (THD) are analyzed compared with the previous full-bridge and clamp-double architectures. An appropriate fault blocking procedure is presented, and a typical four-terminal dc transmission simulation system is given in the power system simulation software. Finally, simulation of steady-state and dc bipolar short-circuit fault verifies that the MTDC system based on this new hybrid MMC topology is stabilized and can block the dc fault and return the nonfault parts to normal.
RECORD: Reference-Assisted Genome Assembly for Closely Related Genomes
Authors: Buza Krisztian , Wilczynski Bartek , Dojer Norbert
Published: October 2015

Background. Next-generation sequencing technologies are now producing multiple times the genome size in total reads from a single experiment. This is enough information to reconstruct at least some of the differences between the individual genome studied in the experiment and the reference genome of the species. However, in most typical protocols, this information is disregarded and the reference genome is used.Results. We provide a new approach that allows researchers to reconstruct genomes very closely related to the reference genome (e.g., mutants of the same species) directly from the reads used in the experiment. Our approach applies de novo assembly software to experimental reads and so-called pseudoreads and uses the resulting contigs to generate a modified reference sequence. In this way, it can very quickly, and at no additional sequencing cost, generate new, modified reference sequence that is closer to the actual sequenced genome and has a full coverage. In this paper, we describe our approach and test its implementation called RECORD. We evaluate RECORD on both simulated and real data. We made our software publicly available on sourceforge.Conclusion. Our tests show that on closely related sequences RECORD outperforms more general assisted-assembly software.
Globally Asymptotic Stability of Stochastic Nonlinear Systems by the Output Feedback
Authors: Cheng Wenwen , Zhu Quanxin , Yao Zhangsong
Published: October 2015

We address the problem of the globally asymptotic stability for a class of stochastic nonlinear systems with the output feedback control. By using the backstepping design method, a novel dynamic output feedback controller is designed to ensure that the stochastic nonlinear closed-loop system is globally asymptotically stable in probability. Our way is different from the traditional mathematical induction method. Indeed, we develop a new method to study the globally asymptotic stability by introducing a series of specific inequalities. Moreover, an example and its simulations are given to illustrate the theoretical result.
Effect ofα-Allocryptopine on Delayed Afterdepolarizations and Triggered Activities in Mice Cardiomyocytes Treated with Isoproterenol
Authors: Xu Bin , Fu Yicheng , Liu Li , Lin Kun , Zhao Xiaojing , Zhang Yu , Chen Xi , Cai Zhongqi , Huang Yun , Li Yang
Published: October 2015

Objective. To investigate the effect ofα-allocryptopine (ALL) on delayed afterdepolarization (DAD) incidence and triggered activity (TA) in mice administered isoproterenol (ISO).Methods. Mouse ventricular myocytes were isolated. And the cellular electrophysiological properties of ventricular myocytes were investigated.Results. We found that the incidences of DADs and TA in mouse myocytes were increased by ISO treatment. In sharp contrast, triggered arrhythmia events were rarely observed in myocytes with 10 μM ALL treatment. Transient inward current (Iti) was reduced significantly with ALL treatment, which contributed to DAD-related triggered arrhythmia. Compared to Iso-treated group, the L-type calcium current (ICa,L) densities were decreased after exposure to ALL, along with slower activation, quicker inactivation, and longer time constant of recovery from inactivation kinetics.Conclusion. There is less triggered arrhythmia events in ventricular myocytes treated with ALL. This effect may be associated with the inhibition ofItiandICa,L.
CO2 Storage Properties of Nanostructured Carbons by a Microwave Plasma Reactor
Authors: Tian Mi , Shang Congxiao
Published: October 2015

Nanostructured carbon was successfully produced by methane cracking in a relatively low‐energy cold plasma reactor designed in‐house. A followed thermal treatment was carried out to further enhance its porosity. The modified plasma carbon was then employed for CO2 adsorption at 25°C. The as‐synthesized plasma carbon and the modified carbon were characterized by BET surface area/pore size analyzer, Raman spectra, and transmission electron microscopy (TEM). The results show thermal modification pronouncedly improves BET surface area and porosity of PC due to opening up of accessible micro‐/mesopores in the graphitic structure and by the removal of amorphous carbons around the graphite surface. The modified PC displays a higher adsorption capacity at 25°C than that of the commercial activated carbon reported. The low hydrogen storage capacity of the modified PC indicates that it can be considered for CO2 removal in syngas.
Development of a Learner Profiling System Using Multidimensional Characteristics Analysis
Authors: Park Kinam , Ji Hyesung , Lim Heuiseok
Published: October 2015

We propose a learner profiling system that uses the multidimensional characteristic analysis of learners. For this purpose, a real-time monitoring system for learners was developed and then used to extract information of the characteristics of learners that appear in learning environments. The extracted information on the characteristics of learners is automatically constructed into personalized learner profiles through the learner profiling system. The contents of learner profiles consist of the cognitive ability of learners, the learning condition, and teacher assessment. To verify the effectiveness of the proposed study method, profiles of actual learners were constructed, with 210 elementary school students as subjects. As a result, the group that learned using the learner profiling showed a significant level of satisfaction in comparison to the group that did not use learner profiling. From this, it was demonstrated that the learner profiling system proposed in this paper could enhance learning effectiveness.
Controlled Synthesis of Hierarchically Assembled Porous ZnO Microspheres with Enhanced Gas‐Sensing Properties
Authors: You Shengsheng , Song Haojie , Qian Jing , Sun Ya-li , Jia Xiao-hua
Published: October 2015

The ZnO microspheres constructed by porous nanosheets were successfully synthesized by calcinating zinc hydroxide carbonate (ZHC) microspheres obtained by a sample hydrothermal method. The samples were characterized in detail with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray diffraction (XRD), and thermogravimetric and differential scanning calorimetry (TG‐DSC). The results indicated that the prepared ZnO microspheres were well crystalline with wurtzite hexagonal phase. The effects of reaction time, temperature, the amount of trisodium citrate, and urea on the morphology of ZnO microspheres were studied. The formation mechanism of porous ZnO microspheres was discussed. Furthermore, the gas‐sensing properties for detection of organic gas of the prepared porous ZnO microspheres were investigated. The results indicated that the prepared porous ZnO microspheres exhibited high gas‐sensing properties for detection of ethanol gas.
Maximum Principle for Forward-Backward Stochastic Control System Driven by Lévy Process
Authors: Wang Xiangrong , Huang Hong
Published: October 2015

We study a stochastic optimal control problem where the controlled system is described by a forward-backward stochastic differential equation driven by Lévy process. In order to get our main result of this paper, the maximum principle, we prove the continuity result depending on parameters about fully coupled forward-backward stochastic differential equations driven by Lévy process. Under some additional convexity conditions, the maximum principle is also proved to be sufficient. Finally, the result is applied to the linear quadratic problem.
Rheological Behavior of Renewable Polyethylene (HDPE) Composites and Sponge Gourd (Luffa cylindrica) Residue
Authors: Escócio Viviane Alves , Pacheco Elen Beatriz Acordi Vasques , Silva Ana Lucia Nazareth da , Cavalcante André de Paula , Visconte Leila Léa Yuan
Published: October 2015

The present study reports the results of rheological behavior of renewable composites, based on a matrix of high density polyethylene (HDPE), made from ethanol distilled from sugarcane, and lignocellulose filler from waste generated in the processing of sponge gourds for bathing use. The composites were prepared with 10, 20, 30, and 40%wt of filler in a twin-screw extruder. The materials were analyzed in a parallel plate rheometer and a melt-flow indexer. The composite morphology was determined by scanning electron microscopy. The composite viscosity increased with filler content, suggesting possible formation of filler agglomerates. This result was confirmed by Cole-Cole diagrams.
Prediction on Droplet Sauter Mean Diameter in Gas-Liquid Mist Flow Based on Droplet Fractal Theory
Authors: Liu Jian-Yi , Tan Xiao-Hua , Fan Zhou , You Xu-Tao , Li Zhou , Zhao Jia-Hui
Published: October 2015

We present a fractal model for droplet Sauter mean diameter in gas-liquid mist flow, based on the droplet fractal theory and the balance relationship between total droplet surface energy and total gas turbulent kinetic energy. The present model is expressed as functions of the droplet fractal dimension, gas superficial velocity, liquid superficial velocity, and other fluid characteristics. Agreement between the present model predictions and experimental measurements is obtained. Results verify the reliability of the present model.
Auditing of Monitoring and Respiratory Support Equipment in a Level III-C Neonatal Intensive Care Unit
Authors: Bergon-Sendin Elena , Perez-Grande Carmen , Lora-Pablos David , De la Cruz Bertolo Javier , Moral-Pumarega María Teresa , Bustos-Lozano Gerardo , Pallas-Alonso Carmen Rosa
Published: October 2015

Background. Random safety audits (RSAs) are a safety tool but have not been widely used in hospitals.Objectives. To determine the frequency of proper use of equipment safety mechanisms in relation to monitoring and mechanical ventilation by performing RSAs. The study also determined whether factors related to the patient, time period, or characteristics of the area of admission influenced how the device safety systems were used.Methods. A prospective observational study was conducted in a level III-C Neonatal Intensive Care Unit (NICU) during 2012. 87 days were randomly selected. Appropriate overall use was defined when all evaluated variables were correctly programmed in the audited device.Results. A total of 383 monitor and ventilator audits were performed. The Kappa coefficient of interobserver agreement was 0.93. The rate of appropriate overall use of the monitors and respiratory support equipment was 33.68%. Significant differences were found with improved usage during weekends, OR 1.85 (1.12–3.06,p=0.01), and during the late shift (3 pm to 10 pm), OR 1.59 (1.03–2.4,p=0.03).Conclusions. Equipment safety systems of monitors and ventilators are not properly used. To improve patient safety, we should identify which alarms are really needed and where the difficulties lie for the correct alarm programming.