bluuebunny/crossref_metadata_2025 huggingface dataset:
Exact scalable sensitivity analysis for the next release problem
Authors: Harman Mark , Krinke Jens , Medina-Bulo Inmaculada , Palomo-Lozano Francisco , Ren Jian , Yoo Shin
Published: April 2014

The nature of the requirements analysis problem, based as it is on uncertain and often inaccurate estimates of costs and effort, makes sensitivity analysis important. Sensitivity analysis allows the decision maker to identify those requirements and budgets that are particularly sensitive to misestimation. However, finding scalable sensitivity analysis techniques is not easy because the underlying optimization problem is NP-hard. This article introduces an approach to sensitivity analysis based on exact optimization. We implemented this approach as a tool, O
ATSAC
, which allowed us to experimentally evaluate the scalability and applicability of Requirements Sensitivity Analysis (RSA). Our results show that O
ATSAC
scales sufficiently well for practical applications in Requirements Sensitivity Analysis. We also show how the sensitivity analysis can yield insights into difficult and otherwise obscure interactions between budgets, requirements costs, and estimate inaccuracies using a real-world case study.
Ontological access to images of fine art
Authors: Isemann Daniel , Ahmad Khurshid
Published: April 2014

Information retrieval in a knowledge rich domain poses challenges that are different from other domains. The domain of fine arts and cultural heritage is an exemplar of such a domain. The many facets of, and complex interrelations between, works of fine art are not easily addressed by conventional keyword-based approaches or even by structured cataloguing systems. Information retrieval challenges in this domain include: the conversion of existing legacy data into knowledge representations that emulate the semantics of the domain's relationships; and easy access to a robust knowledge representation for users unfamiliar with query languages. Our research addresses aspects of both challenges as they are connected and may benefit from being addressed in conjunction. Based on a study on user preferences in art image search and a review of existing structured resources for cataloguing art and heritage information, we have developed two prototypes:
Ontology Populator
and
Artfinder
. The first prototype,
Ontology Populator
, is used to automatically enrich data akin to legacy data kept by heritage institutions and transform it into a knowledge base. The second prototype is a graphical query builder,
Artfinder
, which interacts with the knowledge base. The
Artfinder
interface, is constructed dynamically from the structure of the underlying knowledge. A task-based evaluation of
Artfinder
was carried out with 10 expert and 10 layperson evaluators. Participants reviewed the interface favourably and the evaluation also revealed potential for improvement.
Artfinder
and its “query logic,” perhaps is a semantically richer mode of accessing knowledge repositories, allowing for logically more complex queries than are currently supported outside the realm of dedicated query languages. We believe that domain experts and perhaps informed laypersons will benefit from this retrieval approach.
Implementation and evaluation of mixed-criticality scheduling approaches for sporadic tasks
Authors: Huang Huang-Ming , Gill Christopher , Lu Chenyang
Published: April 2014

Traditional fixed-priority scheduling analysis for periodic and sporadic task sets is based on the assumption that all tasks are equally critical to the correct operation of the system. Therefore, every task has to be schedulable under the chosen scheduling policy, and estimates of tasks' worst-case execution times must be conservative in case a task runs longer than is usual. To address the significant underutilization of a system's resources under normal operating conditions that can arise from these assumptions, several
mixed-criticality scheduling
approaches have been proposed. However, to date, there have been few quantitative comparisons of system schedulability or runtime overhead for the different approaches.

In this article, we present a side-by-side implementation and evaluation of the known mixed-criticality scheduling approaches, for periodic and sporadic mixed-criticality tasks on uniprocessor systems, under a mixed-criticality scheduling model that is common to all these approaches. To make a fair evaluation of mixed-criticality scheduling, we also address previously open issues and propose modifications to improve particular approaches. Our empirical evaluations demonstrate that user-space implementations of mechanisms to enforce different mixed-criticality scheduling approaches can be achieved atop Linux without kernel modification, with reasonably low (but in some cases nontrivial) overhead for mixed-criticality real-time task sets.
A Unified WCET analysis framework for multicore platforms
Authors: Chattopadhyay Sudipta , Chong Lee Kee , Roychoudhury Abhik , Kelter Timon , Marwedel Peter , Falk Heiko
Published: April 2014

With the advent of multicore architectures, worst-case execution time (WCET) analysis has become an increasingly difficult problem. In this article, we propose a unified WCET analysis framework for multicore processors featuring both shared cache and shared bus. Compared to other previous works, our work differs by modeling the interaction of shared cache and shared bus with other basic microarchitectural components (e.g., pipeline and branch predictor). In addition, our framework does not assume a
timing anomaly free
multicore architecture for computing the WCET. A detailed experiment methodology suggests that we can obtain reasonably tight WCET estimates in a wide range of benchmark programs.
An effective grouping scheme for avoiding hidden node problem in IEEE 802.15.4-based wireless sensor networks
Authors: Tseng Hsueh-Wen , Fan Yao-Chung , Sheu Shiann-Tsong , Ou Shaiu-Yi
Published: April 2014

IEEE 802.15.4 standard is designed to achieve low-power transmissions in low-rate and short-distance wireless personal area networks (WPANs). For power consumption consideration, IEEE 802.15.4 uses the modified CSMA/CA protocol and does not have the hidden node protection mechanism, such as RTS/CTS mechanism. Previous studies indicated that the probability of any two nodes in an infrastructure network unheard of each other is around 41%. Therefore, the hidden node problem (HNP) results in inefficient data transmission and serious power consumption issues in WPAN. In this paper, we propose an efficient scheme to avoid the HNP. The idea is to perform hidden node relationship collection for all nodes and then allocate the hidden nodes into different groups with mutually non-overlapping schedules to transmit their frames. The proposed scheme partitions the time of a superframe into several subperiods, and the length of subperiod depends on the number of hidden nodes in a group. Simulation results demonstrate that the proposed scheme not only avoids the HNP but also outperforms the performance of IEEE 802.15.4 standard.
A multi-sensor approach for fall risk prediction and prevention in elderly
Authors: Majumder Akm Jahangir Alam , Zerin Ishmat , Ahamed Sheikh Iqbal , Smith Roger O.
Published: April 2014

Scientific research on smartphone-based fall detection systems has recently been stimulated due to the growing elderly population and their risk of falls. Even though these systems are helpful for fall detection, the best way to reduce the number of falls and their consequences is to predict and prevent them from happening in the first place. To address the issue of fall prevention, in this paper, we propose a fall prediction system by integrating the sensor data of smartphones with a smartshoe. In our previous research, we designed and implemented a pair of sensing shoes (smartshoe) that contained four pressure sensors with a Wi-Fi communication module in each shoe to unobtrusively collect data in any environment. After assimilating the smartshoe and smartphone sensor data, we performed an extensive set of experiments in the lab environment to evaluate normal and abnormal walking patterns. In the smartphone, the system can generate an alert message to warn the user about the high-risk gait patterns and potentially save them from a forthcoming fall. We validated our approach using a decision tree with 10-fold cross validation and found 97.2% accuracy in gait abnormality detection.
Network utility maximization in two-way flow scenario
Authors: Ge Fei , Tan Liansheng
Published: April 2014

A communication network usually has data packets and acknowledge (ACK) packets being transmitted in opposite directions. ACK packet flows may affect the performance of data packet flows, which is unfortunately not considered in the usual network utility maximization (NUM) model. This paper presents a NUM model in networks with two-way flows (NUMtw) by adding a routing matrix to cover ACK packet flows. The source rates are obtained by solving the dual model and the relation to the routing matrix of ACK packet flows is disclosed. Furthermore, the source rates in networks with one-way flows by the usual NUM model are compared to those in networks with two-way flows by the NUMtw model.
IP address multiplexing for VEEs
Authors: Singh Rayman Preet , Brecht Tim , Keshav Srinivasan
Published: April 2014

The number of publicly accessible virtual execution environments (VEEs) has been growing steadily in the past few years. To be accessible by clients, such VEEs need either a public IPv4 or a public IPv6 address. However, the pool of available public IPv4 addresses is nearly depleted and the low rate of adoption of IPv6 precludes its use. Therefore, what is needed is a way to share precious IPv4 public addresses among a large pool of VEEs. Our insight is that if an IP address is assigned at the time of a client DNS request for the VEE's name, it is possible to share a single public IP address amongst a set of VEEs whose workloads are not network intensive, such as those hosting personal servers or performing data analytics. We investigate several approaches to multiplexing a pool of global IP addresses among a large number of VEEs, and design a system that overcomes the limitations of current approaches. We perform a qualitative and quantitative comparison of these solutions. We find that upon receiving a DNS request from a client, our solution has a latency as low as 1 ms to allocate a public IP address to a VEE, while keeping the size of the required IP address pool close to the minimum possible.
OpenState
Authors: Bianchi Giuseppe , Bonola Marco , Capone Antonio , Cascone Carmelo
Published: April 2014

Software Defined Networking envisions smart centralized controllers governing the forwarding behavior of dumb low-cost switches. But are "dumb" switches an actual strategic choice, or (at least to some extent) are they a consequence of the lack of viable alternatives to OpenFlow as programmatic data plane forwarding interface? Indeed, some level of (programmable) control logic in the switches might be beneficial to offload logically centralized controllers (de facto complex distributed systems) from decisions
just
based on local states (versus network-wide knowledge), which could be handled at wire speed
inside
the device itself. Also, it would reduce the amount of flow processing tasks currently delegated to specialized middleboxes. The underlying challenge is: can we devise a
stateful
data plane programming abstraction (versus the stateless OpenFlow match/action table) which still entails high performance and remains consistent with the vendors' preference for closed platforms? We posit that a promising answer revolves around the usage of extended finite state machines, as an extension (super-set) of the OpenFlow match/action abstraction. We concretely turn our proposed abstraction into an actual table-based API, and, perhaps surprisingly, we show how it can be supported by (mostly) reusing core primitives already implemented in OpenFlow devices.
Errata for: Estimating internet address space usage through passive measurements (SIGCOMM CCR (Vol. 44, Issue 1, January, 2014)
Authors: Dainotti Alberto , Benson Karyn , King Alistair , claffy kc , Kallitsis Michael , Glatz Eduard , Dimitropoulos Xenofontas
Published: April 2014

One challenge in understanding the evolution of Internet in- frastructure is the lack of systematic mechanisms for monitoring the extent to which allocated IP addresses are actually used. Address utilization has been monitored via actively scanning the entire IPv4 address space. We evaluate the potential to leverage passive network traffic measurements in addition to or instead of active probing. Passive traffic measurements introduce no network traffic overhead, do not rely on unfiltered responses to probing, and could potentially apply to IPv6 as well. We investigate two challenges in using passive traffic for address utilization inference: the limited visibility of a single observation point; and the presence of spoofed IP addresses in packets that can distort results by implying faked addresses are active. We propose a methodology for removing such spoofed traf- fic on both darknets and live networks, which yields results comparable to inferences made from active probing. Our preliminary analysis reveals a number of promising findings, including novel insight into the usage of the IPv4 address space that would expand with additional vantage points.
Adaptive Sliding Mode Control of MEMS Gyroscope Based on Neural Network Approximation
Authors: Yang Yuzheng , Fei Juntao
Published: April 2014

An adaptive sliding controller using radial basis function (RBF) network to approximate the unknown system dynamics microelectromechanical systems (MEMS) gyroscope sensor is proposed. Neural controller is proposed to approximate the unknown system model and sliding controller is employed to eliminate the approximation error and attenuate the model uncertainties and external disturbances. Online neural network (NN) weight tuning algorithms, including correction terms, are designed based on Lyapunov stability theory, which can guarantee bounded tracking errors as well as bounded NN weights. The tracking error bound can be made arbitrarily small by increasing a certain feedback gain. Numerical simulation for a MEMS angular velocity sensor is investigated to verify the effectiveness of the proposed adaptive neural control scheme and demonstrate the satisfactory tracking performance and robustness.
Enhanced Loop Structure of NFC Antenna for Mobile Handset Applications
Authors: Lee Byungje , Kim Byeongkwan , Yang Sunghyun
Published: April 2014

A new structure of an NFC loop antenna for mobile handset applications is proposed. The proposed antenna consists of conventional loop elements and a parasitic loop embedded capacitor to enhance its performance. Although the sintered ferrite sheets with higher relative permeability(μr≈200)have been used to reduce the performance deterioration due to the eddy current on the battery pack of a mobile handset, their costs are high, and they are considerably breakable. In this paper, with the proposed structure, we effectively enhance the performance of an NFC loop antenna by employing the ferrite-polymer composite with lower relative permeability(μr≈55).
Radix Astragali Improves Dysregulated Triglyceride Metabolism and Attenuates Macrophage Infiltration in Adipose Tissue in High-Fat Diet-Induced Obese Male Rats through Activating mTORC1-PPARγSignaling Pathway
Authors: Long Yang , Zhang Xiang-Xun , Chen Tao , Gao Yun , Tian Hao-Ming
Published: April 2014

Increased levels of free fatty acids (FFAs) and hypertriglyceridemia are important risk factors for cardiovascular disease. The effective fraction isolated from radix astragali (RA) has been reported to alleviate hypertriglyceridemia. The mechanism of this triglyceride-lowering effect of RA is unclear. Here, we tested whether activation of the mTORC1-PPARγsignaling pathway is related to the triglyceride-lowering effect of RA. High-fat diet-induced obese (DIO) rats were fed a high-fat diet (40% calories from fat) for 9-10 weeks, and 4 g/kg/d RA was administered by gavage. RA treatment resulted in decreased fasting triglyceride levels, FFA concentrations, and adipocyte size. RA treated rats showed improved triglyceride clearance and fatty acid handling after olive oil overload. RA administration could also decrease macrophage infiltration and expression of MCP-1 and TNFα, but it may also increase the expression of PPARγin epididymal adipose tissue from RA treated rats. Consistently, expressions of PPARγand phospho-p70S6K were increased in differentiated 3T3-L1 adipocytes treated with RA. Moreover, RA couldnot upregulate the expression of PPARγat the presence of rapamycin. In conclusion, the mTORC1-PPARγsignaling pathway is a potential mechanism through which RA exerts beneficial effects on the disturbance of triglyceride metabolism and dysfunction of adipose tissue in DIO rats.
Studies on Structural and Conducting Properties of Goethite Nanoparticles Doped HPMC Polymer Films
Authors: Urs Thejas Gopal Krishne , Dasaiah Mahadevaiah , Somashekar Rudrappa
Published: April 2014

We have carried out systematic studies on Goethite nanoparticles doped (dispersed) HPMC polymer films to quantify the changes in their structural properties, the conductivity, and IR absorbance of films. It is observed that the addition of nanoparticles has significant influence on changing structural parameters and hence enhancing the conductivity of the polymer composite considerably. These polymer composites are water soluble.
Multiple Solutions for the Discretep-Laplacian Boundary Value Problems
Authors: Long Yuhua , Shi Haiping
Published: April 2014

By employing a critical point theorem, established by Bonanno, we prove the existence of three distinct solutions to boundary value problems of nonlinear difference equations with a discretep-Laplacian operator. To demonstrate the applicability of our results, we also present an example.
Adaptive Robust Actuator Fault Accommodation for a Class of Uncertain Nonlinear Systems with Unknown Control Gains
Authors: Wu Yuefei , Ma Dawei , Yao Jianyong , Le Guigao , Mu Zhenxing , Yang Fan
Published: April 2014

An adaptive robust fault tolerant control approach is proposed for a class of uncertain nonlinear systems with unknown signs of high‐frequency gain and unmeasured states. In the recursive design, neural networks are employed to approximate the unknown nonlinear functions, K‐filters are designed to estimate the unmeasured states, and a dynamical signal and Nussbaum gain functions are introduced to handle the unknown sign of the virtual control direction. By incorporating the switching function σ algorithm, the adaptive backstepping scheme developed in this paper does not require the real value of the actuator failure. It is mathematically proved that the proposed adaptive robust fault tolerant control approach can guarantee that all the signals of the closed‐loop system are bounded, and the output converges to a small neighborhood of the origin. The effectiveness of the proposed approach is illustrated by the simulation examples.
Multiscale Asymptotic Analysis and Parallel Algorithm of Parabolic Equation in Composite Materials
Authors: Wang Xin , Duan Xi-liang , Gao Yang
Published: April 2014

An efficient parallel multiscale numerical algorithm is proposed for a parabolic equation with rapidly oscillating coefficients representing heat conduction in composite material with periodic configuration. Instead of following the classical multiscale asymptotic expansion method, the Fourier transform in time is first applied to obtain a set of complex‐valued elliptic problems in frequency domain. The multiscale asymptotic analysis is presented and multiscale asymptotic solutions are obtained in frequency domain which can be solved in parallel essentially without data communications. The inverse Fourier transform will then recover the approximate solution in time domain. Convergence result is established. Finally, a novel parallel multiscale FEM algorithm is proposed and some numerical examples are reported.
On a Homotopy Perturbation Treatment of Steady Laminar Forced Convection Flow over a Nonlinearly Stretching Porous Sheet
Authors: Dalir Nemat , Nourazar Salman
Published: April 2014

The steady two-dimensional laminar forced convection boundary layer flow of an incompressible viscous Newtonian fluid over a nonlinearly stretching porous (permeable) sheet with suction is considered. The sheet’s permeability is also considered to be nonlinear. The boundary layer equations are transformed by similarity transformations to a nonlinear ordinary differential equation (ODE). Then the homotopy perturbation method (HPM) is used to solve the resultant nonlinear ODE. The dimensionless entrainment parameter and the dimensionless sheet surface shear stress are obtained for various values of the suction parameter and the nonlinearity factor of sheet stretching and permeability. The results indicate that the dimensionless sheet surface shear stress decreases with the increase of suction parameter. The results of present HPM solution are compared to the values obtained in a previous study by the homotopy analysis method (HAM). The HPM results show that they are in good agreement with the HAM results within 2% error.
Norm Attaining Arens Extensions onℓ1
Authors: Falcó Javier , García Domingo , Maestre Manuel , Rueda Pilar
Published: April 2014

We study norm attaining properties of the Arens extensions of multilinear forms defined on Banach spaces. Among other related results, we construct a multilinear form onℓ1with the property that only some fixed Arens extensions determined a priori attain their norms. We also study when multilinear forms can be approximated by ones with the property that only some of their Arens extensions attain their norms.
Localization of Outdoor Mobile Robots Using Curb Features in Urban Road Environments
Authors: Lee Hyunsuk , Park Jooyoung , Chung Woojin
Published: April 2014

Urban road environments that have pavement and curb are characterized as semistructured road environments. In semistructured road environments, the curb provides useful information for robot navigation. In this paper, we present a practical localization method for outdoor mobile robots using the curb features in semistructured road environments. The curb features are especially useful in urban environment, where the GPS failures take place frequently. A curb extraction is conducted on the basis of the Kernel Fisher Discriminant Analysis (KFDA) to minimize false detection. We adopt the Extended Kalman Filter (EKF) to combine the curb information with odometry and Differential Global Positioning System (DGPS). The uncertainty models for the sensors are quantitatively analyzed to provide a practical solution.
Fault Diagnosis of Rotating Machinery Based on Multisensor Information Fusion Using SVM and Time-Domain Features
Authors: Jiang Ling-li , Yin Hua-kui , Li Xue-jun , Tang Si-wen
Published: April 2014

Multisensor information fusion, when applied to fault diagnosis, the time-space scope, and the quantity of information are expanded compared to what could be acquired by a single sensor, so the diagnostic object can be described more comprehensively. This paper presents a methodology of fault diagnosis in rotating machinery using multisensor information fusion that all the features are calculated using vibration data in time domain to constitute fusional vector and the support vector machine (SVM) is used for classification. The effectiveness of the presented methodology is tested by three case studies: diagnostic of faulty gear, rolling bearing, and identification of rotor crack. For each case study, the sensibilities of the features are analyzed. The results indicate that the peak factor is the most sensitive feature in the twelve time-domain features for identifying gear defect, and the mean, amplitude square, root mean square, root amplitude, and standard deviation are all sensitive for identifying gear, rolling bearing, and rotor crack defect comparatively.
Influence of Trash-Barriering on Operation of Pumping Station with Wet-Pits
Authors: Qiu Baoyun , He Shuquan , Chu Shiji , Feng Xiaoli
Published: April 2014

Trash racks are set before inlet sumps of a pumping station with wet-pits in order to block trash. The flow fields before and behind the trash rack were numerically simulated and flow fields in the inlet sump were calculated using the simulated velocity distribution of the section behind the trash rack as the inlet boundary condition. Local head loss of trash-barriering increases with the increase of blockage ratio of the trash rack. When waterweeds block upper part of the trash rack, flow pattern behind the trash rack will be extremely turbulent, flow velocity of lower part of inlet section of inlet sump will increase, flow velocity of the upper part will decrease, and even backflow appears, which will deteriorate the flow pattern and increase head loss in the inlet sump. Trash-barriering has little effect on velocity distribution of impeller inlet section. Trash-barriering will not only increase head and power of the pump but also decrease the flow. For the example of the pumping station: when blockage ratios of the trash racks are 0.3, 0.5, and 0.7, operating cost will increase by 13%~43% than that of without trash racks. Therefore, the trash rack should be cleaned up timely.
A Low-Profile WLAN Antenna with Inductor and Tuning Stub for Broadband Impedance Matching
Authors: Kim Woo-Su , Choi Sunho , Jeong Gye-Taek
Published: April 2014

This paper presents a low-profile multiband antenna suitable for wireless local area networks (WLANs), using a chip inductor and tuning stub for broadband impedance matching. The proposed antenna is compact12×10×1 mm3and covers three bands: 2.4-GHz (2.400–2.484 GHz), 5.2-GHz (5.150–5.350 GHz), and 5.8-GHz (5.725–5.825 GHz). The measured 10-dB bandwidths are 12.0% (2.28–2.57 GHz) in the lower band for 2.4-GHz WLANs and 39.1% (4.81–7.15 GHz) in the upper band for 5 GHz-WLANs. The measured peak gain of the antenna is between 2.7 and 4.39 dBi and the radiation patterns are omnidirectional.
Classifying Normal and Abnormal Status Based on Video Recordings of Epileptic Patients
Authors: Li Jing , Zhen Xiantong , Liu Xianzeng , Ouyang Gaoxiang
Published: April 2014

Based on video recordings of the movement of the patients with epilepsy, this paper proposed a human action recognition scheme to detect distinct motion patterns and to distinguish the normal status from the abnormal status of epileptic patients. The scheme first extracts local features and holistic features, which are complementary to each other. Afterwards, a support vector machine is applied to classification. Based on the experimental results, this scheme obtains a satisfactory classification result and provides a fundamental analysis towards the human-robot interaction with socially assistive robots in caring the patients with epilepsy (or other patients with brain disorders) in order to protect them from injury.
First Radio Astronomy Examination of the Low-Frequency Broadband Active Antenna Subarray
Authors: Stanislavsky A. A. , Bubnov I. N. , Konovalenko A. A. , Gridin A. A. , Shevchenko V. V. , Stanislavsky L. A. , Mukha D. V. , Koval A. A.
Published: April 2014

We present the 25-element active antenna array and its remote control in the framework of the GURT project, the Ukrainian Radio Telescope of a new age. To implement beamforming, the array is phased with the help of discrete cable delay lines in analog manner. The remote control of the array is carried out through the paired encoder and decoder that can transmit parallel data about antenna codes serially. The microcontroller provides the online interaction between personal computer and beamformers with the help of the encoder-decoder system through wires or wireless. The antenna pattern has been measured by radio astronomy methods.
Existence and Monotone Iteration of Positive Pseudosymmetric Solutions for a Third-Order Four-Point BVP
Authors: Lv Xuezhe , Wang Libo , Pei Minghe
Published: April 2014

We study the existence and monotone iteration of solutions for a third-order four-point boundary value problem. An existence result of positive, concave, and pseudosymmetric solutions and its monotone iterative scheme are established by using the monotone iterative technique. Meanwhile, as an application of our results, an example is given.
A Novel Approach for Shearer Cutting Load Identification through Integration of Improved Particle Swarm Optimization and Wavelet Neural Network
Authors: Wang Zhongbin , Si Lei , Tan Chao , Liu Xinhua
Published: April 2014

In order to accurately identify the change of shearer cutting load, a novel approach was proposed through integration of improved particle swarm optimization and wavelet neural network. An improved updating strategy for inertia weight was presented to avoid falling into the local optimum. Moreover, immune mechanism was applied in the proposed approach to enhance the population diversity and improve the quality of solution, and the flowchart of the proposed approach was designed. Furthermore, a simulation example was carried out and comparison results indicated that the proposed approach was feasible, efficient, and outperforming others. Finally, an industrial application example of coal mining face was demonstrated to specify the effect of the proposed system.
Stability and Hopf Bifurcation in a Delayed Predator-Prey System with Herd Behavior
Authors: Xu Chaoqun , Yuan Sanling
Published: April 2014

A special predator-prey system is investigated in which the prey population exhibits herd behavior in order to provide a self-defense against predators, while the predator is intermediate and its population shows individualistic behavior. Considering the fact that there always exists a time delay in the conversion of the biomass of prey to that of predator in this system, we obtain a delayed predator-prey model with square root functional response and quadratic mortality. For this model, we mainly investigate the stability of positive equilibrium and the existence of Hopf bifurcation by choosing the time delay as a bifurcation parameter.
Agrobacterium-Mediated Transformation of the RecalcitrantVandaKasem's Delight Orchid with Higher Efficiency
Authors: Gnasekaran Pavallekoodi , James Antony Jessica Jeyanthi , Uddain Jasim , Subramaniam Sreeramanan
Published: April 2014

The presented study establishedAgrobacterium-mediated genetic transformation using protocorm-like bodies (PLBs) for the production of transgenicVandaKasem's Delight Tom Boykin (VKD) orchid. Several parameters such as PLB size, immersion period, level of wounding,Agrobacteriumdensity, cocultivation period, and concentration of acetosyringone were tested and quantified usinggusAgene expression to optimize the efficiency ofAgrobacterium-mediated genetic transformation of VKD's PLBs. Based on the results, 3-4 mm PLBs wounded by scalpel and immersed for 30 minutes inAgrobacteriumsuspension of 0.8 unit atA600nmproduced the highest GUS expression. Furthermore, cocultivating infected PLBs for 4 days in the dark on Vacin and Went cocultivation medium containing 200 𝜇M acetosyringone enhanced the GUS expression. PCR analysis of the putative transformants selected in the presence of 250 mg/L cefotaxime and 30 mg/L geneticin proved the presence ofwheatwin1,wheatwin2, andnptIIgenes.
Ag‐Cu Colloid Synthesis: Bimetallic Nanoparticle Characterisation and Thermal Treatment
Authors: Sopoušek Jiří , Pinkas Jiří , Brož Pavel , Buršík Jiří , Vykoukal Vít , Škoda David , Stýskalík Aleš , Zobač Ondřej , Vřešťál Jan , Hrdlička Aleš , Šimbera Jan
Published: April 2014

The Ag‐Cu bimetallic colloidal nanoparticles (NPs) were prepared by solvothermal synthesis from metalloorganic precursors in a mixture of organic solvents. The nanoparticles were characterized by dynamic light scattering (DLS) and small angle X‐ray scattering (SAXS). The properties of metallic core and organic shell of the nanoparticles were studied by direct inlet probe mass spectrometry (DIP/MS), Knudsen effusion mass spectrometry (KEMS), double‐pulse laser‐induced breakdown spectroscopy (DPLIBS), and differential scanning calorimetry (DSC). The transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used for particle characterization before and after thermal analysis. The experiment yielded results that were for AgCu nanoparticles for the first time. The detected liquidus temperature has been compared with the prediction obtained from calculation of the phase diagram of Ag‐Cu nanoalloy. The experimental results show that of near‐eutectic composition AgCu nanoparticles possess the fcc crystal lattice. Surprisingly, spinodal decomposition was not observed inside the AgCu nanoparticles at temperatures up to 230°C. The depression of the eutectic AgCu melting point was calculated but not observed. The eutectic AgCu microparticles are formed before melting.
Initial Coefficients of Biunivalent Functions
Authors: Lee See Keong , Ravichandran V. , Supramaniam Shamani
Published: April 2014

An analytic functionfdefined on the open unit disk is biunivalent if the functionfand its inversef-1are univalent in𝔻. Estimates for the initial coefficients of biunivalent functionsfare investigated whenfandf-1, respectively, belong to some subclasses of univalent functions. Some earlier results are shown to be special cases of our results.
A Mixed 0‐1 Linear Programming Approach to the Computation of All Pure‐Strategy Nash Equilibria of a Finite n‐Person Game in Normal Form
Authors: Wu Zhengtian , Dang Chuangyin , Karimi Hamid Reza , Zhu Changan , Gao Qing
Published: April 2014

A main concern in applications of game theory is how to effectively select a Nash equilibrium, especially a pure‐strategy Nash equilibrium for a finite n‐person game in normal form. This selection process often requires the computation of all Nash equilibria. It is well known that determining whether a finite game has a pure‐strategy Nash equilibrium is an NP‐hard problem and it is difficult to solve by naive enumeration algorithms. By exploiting the properties of pure strategy and multilinear terms in the payoff functions, this paper formulates a new mixed 0‐1 linear program for computing all pure‐strategy Nash equilibria. To our knowledge, it is the first method to formulate a mixed 0‐1 linear programming for pure‐strategy Nash equilibria and it may work well for similar problems. Numerical results show that the approach is effective and this method can be easily distributed in a distributed way.
Set-Valued Hardy-Rogers Type Contraction in 0-Complete Partial Metric Spaces
Authors: Shukla Satish , Radenović Stojan , Vetro Calogero
Published: April 2014

In this paper we introduce set-valued Hardy-Rogers type contraction in 0-complete partial metric spaces and prove the corresponding theorem of fixed point. Our results generalize, extend, and unify several known results, in particular the recent Nadler’s fixed point theorem in the context of complete partial metric spaces established by Aydi et al. (2012). As an application of our results, a homotopy theorem for such mappings is derived. Also, some examples are included which show that our generalization is proper.
Achieving Distributed Consensus in UWB Sensor Networks: A Low Sampling Rate Scheme with Quantized Measurements
Authors: Taponecco Lorenzo , Sanguinetti Luca
Published: April 2014

Distributed consensus in sensor networks has received great attention in the last few years. Most of the research activity has been devoted to study the sensor interactions that allow the convergence of distributed consensus algorithms toward a globally optimal decision. On the other hand, the problem of designing an appropriate radio interface enabling such interactions has received little attention in the literature. Motivated by the above consideration, in this work an ultrawideband sensor network is considered and a physical layer scheme is designed, which allows the active sensors to achieve consensus in a distributed manner without the need of any admission protocol. We focus on the class of the so-called quantized distributed consensus algorithms in which the local measurements or current states of each sensor belong to a finite set. Particular attention is devoted to address the practical implementation issues as well as to the development of a receiver architecture with the same performance of existing alternatives based on an all-digital implementation but with a much lower sampling frequency on the order of MHz instead of GHz.
Construction of Biholomorphic Convex Mappings of OrderαonBpn
Authors: Liu Ming-Sheng , Yang Fengying , Kou Kit Ian , Huang Changqin
Published: April 2014

Some sufficient conditions for biholomorphic convex mappings of orderαon the Reinhardt domainBpninCnare given; from that, criteria for biholomorphic convex mappings of orderαwith particular form become direct. As applications of these sufficient conditions, some concrete biholomorphic convex mappings of orderα  onBpnare provided.
Dynamic Crack Analysis in Isotropic/Orthotropic Media via Extended Isogeometric Analysis
Authors: Yu Tiantang , Lai Yongling , Yin Shuohui
Published: April 2014

The extended isogeometric analysis (X‐IGA) is the combination of the extended finite element method (X‐FEM) and the isogeometric analysis (IGA), so the X‐IGA possesses the advantages of both methods. In this paper, the X‐IGA is extended to investigate the dynamic stress intensity factors of cracked isotropic/orthotropic media under impact loading. For this purpose, a corresponding dynamic X‐IGA model is developed, the Newmark time integration scheme is used to achieve a dynamic response, and the dynamic stress intensity factors are evaluated through the contour interaction integral technique. Numerical simulations show that the X‐IGA results agree with other available reference solutions, and accurate results can be obtained by using the X‐IGA with a relatively coarse mesh.
A Heuristic Procedure for a Ship Routing and Scheduling Problem with Variable Speed and Discretized Time Windows
Authors: Castillo-Villar Krystel K. , González-Ramírez Rosa G. , Miranda González Pablo , Smith Neale R.
Published: April 2014

This paper develops a heuristic algorithm for solving a routing and scheduling problem for tramp shipping with discretized time windows. The problem consists of determining the set of cargoes that should be served by each ship, the arrival, departure, and waiting times at each port, while minimizing total costs. The heuristic proposed is based on a variable neighborhood search, considering a number of neighborhood structures to find a solution to the problem. We present computational results, and, for comparison purposes, we consider instances that can be solved directly by CPLEX to test the performance of the proposed heuristic. The heuristics achieves good solution quality with reasonable computational times. Our computational results are encouraging and establish that our heuristic can be utilized to solve large real‐size instances.
Validity of Cardiovascular Risk Prediction Models in Kidney Transplant Recipients
Authors: Mansell Holly , Stewart Samuel Alan , Shoker Ahmed
Published: April 2014

Background.Predicting cardiovascular risk is of great interest in renal transplant recipients since cardiovascular disease is the leading cause of mortality.Objective.To conduct a systematic review to assess the validity of cardiovascular risk prediction models in this population.Methods.Five databases were searched (MEDLINE, EMBASE, SCOPUS, CINAHL, and Web of Science) and cohort studies with at least one year of follow-up were included. Variables that described population characteristics, study design, and prognostic performance were extracted. The Quality in Prognostic Studies (QUIPS) tool was used to evaluate bias.Results.Seven studies met the criteria for inclusion, of which, five investigated the Framingham risk score and three used a transplant-specific model. Sample sizes ranged from 344 to 23,575, and three studies lacked sufficient event rates to confidently reach conclusion. Four studies reported discrimination (as measured byc-statistic), which ranged from 0.701 to 0.75, while only one risk model was both internally and externally validated.Conclusion.The Framingham has underestimated cardiovascular events in renal transplant recipients, but these studies have not been robust. A risk prediction model has been externally validated at least on one occasion, but comprehensive validation in multiple cohorts and impact analysis are recommended before widespread clinical application is advocated.
A Less Conservative Stability Criterion for Delayed Stochastic Genetic Regulatory Networks
Authors: Yu Tingting , Wang Jing , Zhang Xian
Published: April 2014

This paper concerns the problem of stability analysis for delayed stochastic genetic regulatory networks. By introducing an appropriate Lyapunov‐Krasovskii functional and employing delay‐range partition approach, a new stability criterion is given to ensure the mean square stability of genetic regulatory networks with time‐varying delays and stochastic disturbances. The stability criterion is given in the form of linear matrix inequalities, which can be easily tested by the LMI Toolbox of MATLAB. Moreover, it is theoretically shown that the obtained stability criterion is less conservative than the one in W. Zhang et al., 2012. Finally, a numerical example is presented to illustrate our theory.
Trends in Computer-Aided Manufacturing in Prosthodontics: A Review of the Available Streams
Authors: Abduo Jaafar , Lyons Karl , Bennamoun Mohammed
Published: April 2014

In prosthodontics, conventional methods of fabrication of oral and facial prostheses have been considered the gold standard for many years. The development of computer-aided manufacturing and the medical application of this industrial technology have provided an alternative way of fabricating oral and facial prostheses. This narrative review aims to evaluate the different streams of computer-aided manufacturing in prosthodontics. To date, there are two streams: the subtractive and the additive approaches. The differences reside in the processing protocols, materials used, and their respective accuracy. In general, there is a tendency for the subtractive method to provide more homogeneous objects with acceptable accuracy that may be more suitable for the production of intraoral prostheses where high occlusal forces are anticipated. Additive manufacturing methods have the ability to produce large workpieces with significant surface variation and competitive accuracy. Such advantages make them ideal for the fabrication of facial prostheses.
Analytical and Numerical Study of the Projective Synchronization of the Chaotic Complex Nonlinear Systems with Uncertain Parameters and Its Applications in Secure Communication
Authors: Abualnaja Kholod M. , Mahmoud Emad E.
Published: April 2014

The main aim of this research is to find an analytical and numerical study to investigate the projective synchronization of two identical or nonidentical chaotic complex nonlinear systems with uncertain parameters. The secure communication between these systems is achieved based on this study. Based on the adaptive control technique and the Lyapunov function a scheme is designed to achieve projective synchronization of chaotic attractors of these systems. The projective synchronization of two identical complex Chen systems and two different chaotic complex Lü and Lorenz systems is taken as two examples to verify the feasibility of the presented scheme. These chaotic complex systems appear in several applications in physics, engineering, and other applied sciences. Numerical simulations are calculated
to demonstrate the effectiveness of the proposed synchronization scheme and verify the theoretical results. The above results will provide theoretical foundation for the secure communication applications based on the proposed scheme.
Antibacterial Potential of Northeastern Portugal Wild Plant Extracts and Respective Phenolic Compounds
Authors: Pinho Eva , Ferreira Isabel C. F. R. , Barros Lillian , Carvalho Ana Maria , Soares Graça , Henriques Mariana
Published: April 2014

The present work aims to assess the antibacterial potential of phenolic extracts, recovered from plants obtained on the North East of Portugal, and of their phenolic compounds (ellagic, caffeic, and gallic acids, quercetin, kaempferol, and rutin), against bacteria commonly found on skin infections. The disk diffusion and the susceptibility assays were used to identify the most active extracts and phenolic compounds. The effect of selected phenolic compounds on animal cells was assessed by determination of cellular metabolic activity. Gallic acid had a higher activity, against gram-positive (S. epidermidisandS. aureus) and gram-negative bacteria (K. pneumoniae) at lower concentrations, than the other compounds. The caffeic acid, also, showed good antibacterial activity against the 3 bacteria used. The gallic acid was effective against the 3 bacteria without causing harm to the animal cells. Gallic and caffeic acid showed a promising applicability as antibacterial agents for the treatment of infected wounds.
Frequency Diverse Array Radar Cramér-Rao Lower Bounds for Estimating Direction, Range, and Velocity
Authors: Wang Yongbing , Wang Wen-Qin , Shao Huaizong
Published: April 2014

Different from phased-array radar, frequency diverse array (FDA) radar offers range-dependent beampattern and thus provides new application potentials. But there is a fundamental question: what estimation performance can achieve for an FDA radar? In this paper, we derive FDA radar Cramér-Rao lower bounds (CRLBs) for estimating direction, range (time delay), and velocity (Doppler shift). Two different data models including pre- and postmatched filtering are investigated separately. As the FDA radar has range-angle coupling, we use a simple transmit subaperturing strategy which divides the whole array into two subarrays, each uses a distinct frequency increment. Assuming temporally white Gaussian noise and linear frequency modulated transmit signal, extensive simulation examples are performed. When compared to conventional phased-array radar, FDA can yield better CRLBs for estimating the direction, range, and velocity. Moreover, the impacts of the element number and frequency increment are also analyzed. Simulation results show that the CRLBs decrease with the increase of the elements number and frequency increment.
A Polymorphism ofORAI1rs7135617, Is Associated with Susceptibility to Rheumatoid Arthritis
Authors: Yen Jeng-Hsien , Chang Che-Mai , Hsu Yu-Wen , Lee Chih-Hung , Wu Mei-Shin , Hwang Daw-Yang , Chen Ben-Kuen , Liao Hsien-Tzung , Wu Man-Tzu Marcie , Chang Wei-Chiao
Published: April 2014

Rheumatoid arthritis (RA), a chronic inflammatory disease usually occurring in synovial tissues and joints, is highly associated with genetic and environmental factors.ORAI1, a gene related to cellular immune system, has been shown to be involved in the pathogenesis of chronic inflammatory diseases and immune diseases. To identify whetherORAI1gene contributes to RA susceptibility, we enrolled 400 patients with RA and 621 healthy individuals for a case-control genetic association study. Five tagging single nucleotides polymorphisms (tSPNs) withinORAI1gene were selected for genotyping. An SNP, rs7135617, showed a significant correlation with the risk of RA. Our results indicated that genetic polymorphism ofORAI1gene is involved in the susceptibility of RA in a Taiwanese population.