bluuebunny/crossref_metadata_2025 huggingface dataset:
Parallel chen-han (PCH) algorithm for discrete geodesics
Authors: Ying Xiang , Xin Shi-Qing , He Ying
Published: February 2014

In many graphics applications, the computation of exact geodesic distance is very important. However, the high computational cost of existing geodesic algorithms means that they are not practical for large-scale models or time-critical applications. To tackle this challenge, we propose the Parallel Chen-Han (or PCH) algorithm, which extends the classic Chen-Han (CH) discrete geodesic algorithm to the parallel setting. The original CH algorithm and its variant both lack a parallel solution because the windows (a key data structure that carries the shortest distance in the wavefront propagation) are maintained in a strict order or a tightly coupled manner, which means that only one window is processed at a time. We propose dividing the CH's sequential algorithm into four phases, window selection, window propagation, data organization, and events processing so that there is no data dependence or conflicts in each phase and the operations within each phase can be carried out in parallel. The proposed PCH algorithm is able to propagate a large number of windows simultaneously and independently. We also adopt a simple yet effective strategy to control the total number of windows. We implement the PCH algorithm on modern GPUs (such as Nvidia GTX 580) and analyze the performance in detail. The performance improvement (compared to the sequential algorithms) is highly consistent with GPU double-precision performance (GFLOPS). Extensive experiments on real-world models demonstrate an order of magnitude improvement in execution time compared to the state-of-the-art.
Extending string similarity join to tolerant fuzzy token matching
Authors: Wang Jiannan , Li Guoliang , Feng Jianhua
Published: February 2014

String similarity join that finds similar string pairs between two string sets is an essential operation in many applications and has attracted significant attention recently in the database community. A significant challenge in similarity join is to implement an effective fuzzy match operation to find all similar string pairs which may not match exactly. In this article, we propose a new similarity function, called
fuzzy-token-matching-based similarity
which extends token-based similarity functions (e.g., jaccard similarity and cosine similarity) by allowing fuzzy match between two tokens. We study the problem of similarity join using this new similarity function and present a signature-based method to address this problem. We propose new signature schemes and develop effective pruning techniques to improve the performance. We also extend our techniques to support weighted tokens. Experimental results show that our method achieves high efficiency and result quality and significantly outperforms state-of-the-art approaches.
Bandwidth adaptation for 3D mesh preview streaming
Authors: Zhao Shanghong , Ooi Wei Tsang , Carlier Axel , Morin Geraldine , Charvillat Vincent
Published: February 2014

Online galleries of 3D models typically provide two ways to preview a model before the model is downloaded and viewed by the user: (i) by showing a set of thumbnail images of the 3D model taken from representative views (or keyviews); (ii) by showing a video of the 3D model as viewed from a moving virtual camera along a path determined by the content provider. We propose a third approach called preview streaming for mesh-based 3D objects: by streaming and showing parts of the mesh surfaces visible along the virtual camera path. This article focuses on the preview streaming architecture and framework and presents our investigation into how such a system would best handle network congestion effectively. We present three basic methods: (a)
stop-and-wait
, where the camera pauses until sufficient data is buffered; (b)
reduce-speed
, where the camera slows down in accordance to reduce network bandwidth; and (c)
reduce-quality
, where the camera continues to move at the same speed but fewer vertices are sent and displayed, leading to lower mesh quality. We further propose two advanced methods: (d)
keyview-aware
, which trades off mesh quality and camera speed appropriately depending on how close the current view is to the keyviews, and (e)
adaptive-zoom
, which improves visual quality by moving the virtual camera away from the original path. A user study reveals that our
keyview-aware
method is preferred over the basic methods. Moreover, the
adaptive-zoom
scheme compares favorably to the
keyview-aware
method, showing that path adaptation is a viable approach to handling bandwidth variation.
Approximating Markov Processes by Averaging
Authors: Chaput Philippe , Danos Vincent , Panangaden Prakash , Plotkin Gordon
Published: February 2014

Normally, one thinks of probabilistic transition systems as taking an initial probability distribution over the state space into a new probability distribution representing the system after a transition. We, however, take a dual view of Markov processes as transformers of bounded measurable functions. This is very much in the same spirit as a “predicate-transformer” view, which is dual to the state-transformer view of transition systems. We redevelop the theory of labelled Markov processes from this viewpoint; in particular, we explore approximation theory. We obtain three main results.

(i) It is possible to define bisimulation on general measure spaces and show that it is an equivalence relation. The logical characterization of bisimulation can be done straightforwardly and generally.

(ii) A new and flexible approach to approximation based on averaging can be given. This vastly generalizes and streamlines the idea of using conditional expectations to compute approximations.

(iii) We show that there is a minimal process bisimulation-equivalent to a given process, and this minimal process is obtained as the limit of the finite approximants.
Synchronous digital circuits as functional programs
Authors: Gammie Peter
Published: February 2014

Functional programming techniques have been used to describe synchronous digital circuits since the early 1980s. Here we survey the systems and formal underpinnings that constitute this tradition. We situate these techniques with respect to other formal methods for hardware design and discuss the work yet to be done.
Monitoring massive appliances by a minimal number of smart meters
Authors: Wang Yongcai , Hao Xiaohong , Song Lei , Wu Chenye , Wang Yuexuan , Hu Changjian , Yu Lu
Published: February 2014

This article presents a framework for deploying a minimal number of smart meters to accurately track the ON/OFF states of a massive number of electrical appliances which exploits the sparseness feature of simultaneous ON/OFF switching events of the massive appliances. A theoretical bound on the least number of required smart meters is studied by an entropy-based approach, which qualifies the impact of meter deployment strategies to the state tracking accuracy. It motivates a meter deployment optimization algorithm (MDOP) to minimize the number of meters while satisfying given requirements to state tracking accuracy. To accurately decode the real-time ON/OFF states of appliances by the readings of meters, a fast state decoding (FSD) algorithm based on the hidden Markov model (HMM) is presented to track the state sequence of each appliance for better accuracy. Although traditional HMM needsO(t22N) time complexity to conduct online sequence decoding, FSD improves the complexity toO(tnU+1), wheren<NandUis an upper bound of the simultaneous switching events. Both MDOP and FSD are verified extensively using simulations and real PowerNet data. The results show that the meter deployment cost can be saved by more than 80% while still getting over 90% state tracking accuracy.
Maintaining real-time application timing similarity for defect-tolerant NoC-based many-core systems
Authors: Li Zheng , Lockom Frank , Ren Shangping
Published: February 2014

Many-core Network-on-Chip (NoC) processors are emerging in broad application areas, including those with timing requirements, such as real-time and multimedia applications. Typically, these processors employ core-level backup to improve yield. However, when defective cores are replaced by backup ones, the NoC topology changes. Consequently, a fine-tuned application based on timing parameters given by one topology may not meet the expected timing behavior under the new one. We first develop a metric to measure timing similarity of an application on different NoC topologies and then propose mixed binary quadratic programming and greedy algorithms to reconfigure a defect-tolerant many-core NoC.
Distributed programming framework for fast iterative optimization in networked cyber-physical systems
Authors: Balani Rahul , Wanner Lucas F. , Srivastava Mani B.
Published: February 2014

Large-scale coordination and control problems in cyber-physical systems are often expressed within the networked optimization model. While significant advances have taken place in optimization techniques, their widespread adoption in practical implementations has been impeded by the complexity of internode coordination and lack of programming support for the same. Currently, application developers build their own elaborate coordination mechanisms for synchronized execution and coherent access to shared resources via distributed and concurrent controller processes. However, they typically tend to be error prone and inefficient due to tight constraints on application development time and cost. This is unacceptable in many CPS applications, as it can result in expensive and often irreversible side-effects in the environment due to inaccurate or delayed reaction of the control system.

This article explores the design of a distributed shared memory (DSM) architecture that abstracts the details of internode coordination. It simplifies application design by transparently managing routing, messaging, and discovery of nodes for coherent access to shared resources. Our key contribution is the design of provably correct locality-sensitive synchronization mechanisms that exploit the spatial locality inherent in actuation to drive faster and scalable application execution through opportunistic data parallel operation. As a result, applications encoded in the proposed Hotline Application Programming Framework are error free, and in many scenarios, exhibit faster reactions to environmental events over conventional implementations.

Relative to our prior work, this article extends Hotline with a new locality-sensitive coordination mechanism for improved reaction times and two tunable iteration control schemes for lower message costs. Our extensive evaluation demonstrates that realistic performance and cost of applications are highly sensitive to the prevalent deployment, network, and environmental characteristics. This highlights the importance of Hotline, which provides user-configurable options to trivially tune these metrics and thus affords time to the developers for implementing, evaluating, and comparing multiple algorithms.
Achieving energy-synchronized communication in energy-harvesting wireless sensor networks
Authors: Gu Yu , He Liang , Zhu Ting , He Tian
Published: February 2014

With advances in energy-harvesting techniques, it is now feasible to build sustainable sensor networks to support long-term applications. Unlike battery-powered sensor networks, the objective of sustainable sensor networks is to effectively utilize a continuous stream of ambient energy. Instead of pushing the limits of energy conservation, we aim to design energy-synchronized schemes that keep energy supplies and demands in balance. Specifically, this work presents Energy-Synchronized Communication (ESC) as a transparent middleware between the network layer and MAC layer that controls the amount and timing of RF activity at receiving nodes. In this work, we first derive a delay model for cross-traffic at individual nodes, which reveals an interesting
stair effect
. This effect allows us to design a localized energy synchronization control with ℴ(
d
3
) time complexity that shuffles or adjusts the working schedule of a node to optimize cross-traffic delays in the presence of changing duty cycle budgets, where
d
is the node degree in the network. Under different rates of energy fluctuations, shuffle-based and adjustment-based methods have different influences on
logical connectivity
and
cross-traffic delay
, due to the inconsistent views of working schedules among neighboring nodes before schedule updates. We study the trade-off between them and propose methods for updating working schedules efficiently. To evaluate our work, ESC is implemented on MicaZ nodes with two state-of-the-art routing protocols. Both testbed experiment and large-scale simulation results show significant performance improvements over randomized synchronization controls.
Energy-efficient task allocation techniques for asymmetric multiprocessor embedded systems
Authors: Elewi Abdullah , Shalan Mohamed , Awadalla Medhat , Saad Elsayed M.
Published: February 2014

Asymmetric multiprocessor systems are considered power-efficient multiprocessor architectures. Furthermore, efficient task allocation (partitioning) can achieve more energy efficiency at these asymmetric multiprocessor platforms. This article addresses the problem of energy-aware static partitioning of periodic real-time tasks on asymmetric multiprocessor (multicore) embedded systems. The article formulates the problem according to the Dynamic Voltage and Frequency Scaling (DVFS) model supported by the platform and shows that it is an NP-hard problem. Then, the article outlines optimal reference partitioning techniques for each case of DVFS model with suitable assumptions. Finally, the article proposes modifications to the traditional bin-packing techniques and designs novel techniques taking into account the DVFS model supported by the platform. All algorithms and techniques are simulated and compared. The simulation shows promising results, where the proposed techniques reduced the energy consumption by 75% compared to traditional methods when DVFS is not supported and by 50% when per-core DVFS is supported by the platform.
Model-Driven Engineering of Self-Adaptive Software with EUREMA
Authors: Vogel Thomas , Giese Holger
Published: February 2014

The development of self-adaptive software requires the engineering of an adaptation engine that controls the underlying adaptable software by feedback loops. The engine often describes the adaptation by runtime models representing the adaptable software and by activities such as analysis and planning that use these models. To systematically address the interplay between runtime models and adaptation activities,
runtime megamodels
have been proposed. A runtime megamodel is a specific model capturing runtime models and adaptation activities. In this article, we go one step further and present an executable modeling language for
ExecUtable RuntimE MegAmodels
(EUREMA) that eases the development of adaptation engines by following a model-driven engineering approach. We provide a domain-specific modeling language and a runtime interpreter for adaptation engines, in particular feedback loops. Megamodels are kept alive at runtime and by interpreting them, they are directly executed to run feedback loops. Additionally, they can be dynamically adjusted to adapt feedback loops. Thus, EUREMA supports development by making feedback loops explicit at a higher level of abstraction and it enables solutions where multiple feedback loops interact or operate on top of each other and self-adaptation co-exists with offline adaptation for evolution.
CAAC -- An Adaptive and Proactive Access Control Approach for Emergencies in Smart Infrastructures
Authors: Venkatasubramanian Krishna K. , Mukherjee Tridib , Gupta Sandeep K. S.
Published: February 2014

The article presents an access control model called
Criticality Aware Access Control
(CAAC) for criticality (emergency) management in smart infrastructures. Criticalities are consequences of events which take a system (in our case, a smart infrastructure) into an unstable state. They require the execution of specific
response actions
in order to bring them under control. The principal aim of CAAC is to grant the right set of access privileges (to facilitate response action execution), at the right time, to the right set of subjects, for the right duration, in order to control the criticalities within the system. In this regard, the CAAC model uses a stochastic model called the
Action Generation Model
to determine the required response actions for the combination of criticalities present within the system. It then facilitates response actions by
adaptively
altering the privileges to specific subjects, in a
proactive
manner, without the need for any explicit access requests. In this article, we formalize the CAAC model and validate it based on two
design goals
- proactivity and adaptiveness. Finally, we present a case study demonstrating CAAC’s operation on an oil-rig platform in order to aid in the response to health- and fire-related criticalities.
A Host-Based Approach for Unknown Fast-Spreading Worm Detection and Containment
Authors: Chen Songqing , Liu Lei , Wang Xinyuan , Zhang Xinwen , Zhang Zhao
Published: February 2014

The fast-spreading worm, which immediately propagates itself after a successful infection, is becoming one of the most serious threats to today’s networked information systems. In this article, we present WormTerminator, a host-based solution for fast Internet worm detection and containment with the assistance of virtual machine techniques based on the fast-worm defining characteristic. In WormTerminator, a virtual machine cloning the host OS runs in parallel to the host OS. Thus, the virtual machine has the same set of vulnerabilities as the host. Any outgoing traffic from the host is diverted through the virtual machine. If the outgoing traffic from the host is for fast worm propagation, the virtual machine should be infected and will exhibit worm propagation pattern very quickly because a fast-spreading worm will start to propagate as soon as it successfully infects a host. To prove the concept, we have implemented a prototype of WormTerminator and have examined its effectiveness against the real Internet worm Linux/Slapper. Our empirical results confirm that WormTerminator is able to completely contain worm propagation in real-time without blocking any non-worm traffic. The major performance cost of WormTerminator is a one-time delay to the start of each outgoing normal connection for worm detection. To reduce the performance overhead, caching is utilized, through which WormTerminator will delay no more than 6% normal outgoing traffic for such detection on average.
Querying Regular Graph Patterns
Authors: Barceló Pablo , Libkin Leonid , Reutter Juan L.
Published: February 2014

Graph data appears in a variety of application domains, and many uses of it, such as querying, matching, and transforming data, naturally result in incompletely specified graph data, that is, graph patterns. While queries need to be posed against such data, techniques for querying patterns are generally lacking, and properties of such queries are not well understood.

Our goal is to study the basics of querying graph patterns. The key features of patterns we consider here are node and label variables and edges specified by regular expressions. We provide a classification of patterns, and study standard graph queries on graph patterns. We give precise characterizations of both data and combined complexity for each class of patterns. If complexity is high, we do further analysis of features that lead to intractability, as well as lower-complexity restrictions. Since our patterns are based on regular expressions, query answering for them can be captured by a new automata model. These automata have two modes of acceptance: one captures queries returning nodes, and the other queries returning paths. We study properties of such automata, and the key computational tasks associated with them. Finally, we provide additional restrictions for tractability, and show that some intractable cases can be naturally cast as instances of constraint satisfaction problems.
A Study of Linux File System Evolution
Authors: Lu Lanyue , Arpaci-Dusseau Andrea C. , Arpaci-Dusseau Remzi H. , Lu Shan
Published: February 2014

We conduct a comprehensive study of file-system code evolution. By analyzing eight years of Linux file-system changes across 5079 patches, we derive numerous new (and sometimes surprising) insights into the file-system development process; our results should be useful for both the development of file systems themselves as well as the improvement of bug-finding tools.
Sector-Disk (SD) Erasure Codes for Mixed Failure Modes in RAID Systems
Authors: Plank James S. , Blaum Mario
Published: February 2014

Traditionally, when storage systems employ erasure codes, they are designed to tolerate the failures of entire disks. However, the most common types of failures are latent sector failures, which only affect individual disk sectors, and block failures which arise through wear on SSD’s. This article introduces SD codes, which are designed to tolerate combinations of disk and sector failures. As such, they consume far less storage resources than traditional erasure codes. We specify the codes with enough detail for the storage practitioner to employ them, discuss their practical properties, and detail an open-source implementation.
Fast parallel GCD algorithm of many integers
Authors: Sedjelmaci Sidi M.
Published: February 2014

We present a new parallel algorithm which computes the GCD of
n
integers of
O
(
n
) bits in
O
(
n
/ log
n
) time with
O
(
n
2+ε
) processors, for any ε > 0 on CRCW PRAM model.
A computer algebra user interface manifesto
Authors: Stoutemyer David R.
Published: February 2014

Many computer algebra systems have more than 1000 built-in functions, making expertise difficult. Using mock dialog boxes, this article describes a proposed interactive general-purpose wizard for organizing optional transformations and allowing easy fine grain control over the form of the result -- even by amateurs. This wizard integrates ideas including:

flexible subexpression selection;

complete control over the ordering of variables and commutative operands, with wellchosen defaults;

interleaving the choice of successively less main variables with applicable function choices to provide detailed control without incurring a combinatorial number of applicable alternatives at any one level;

quick applicability tests to reduce the listing of inapplicable transformations;

using an organizing principle to order the alternatives in a helpful manner;

labeling quickly-computed alternatives in dialog boxes with a preview of their results, using ellipsis elisions if necessary or helpful;

allowing the user to retreat from a sequence of choices to explore other branches of the tree of alternatives -- or to return quickly to branches already visited;

allowing the user to accumulate more than one of the alternative forms;

integrating direct manipulation into the wizard; and

supporting not only the usual input-result pair mode, but also the useful alternative derivational and in situ replacement modes in a unified window.
The new group theory package in Maple 17
Authors: Postma E. J.
Published: February 2014

The GroupTheory package was added to Maple 17 [1]. It deals with discrete groups. The package offers visualizations of group theoretic concepts; accepts input and generates output that is relatively close to the classical textbook notation; and can deal with parameterized groups where the parameters are given only symbolically.
Classifying discrete objects with orbiter
Authors: Betten Anton
Published: February 2014

Orbiter is a software package to classify discrete objects such as designs, graphs, codes, and objects from finite geometry. It employs the method of breaking the symmetry to attack difficult problem instances by means of subobjects that serve as a stepping stone. The algorithms combine techniques from Group Theory and from Combinatorics. Orbiter is a library of C++ functions that provide functionality for Discrete Mathematics. In order to be applied to a specific problem, code has to be written taylored to the specific application.
eLearn Enters a New Era
Authors: Carr-Chellman Alison
Published: February 2014

eLearn Magazine is entering a new era and will look and feel rather different in the coming months. The editor-in-chief shares a preview of what is new and what is coming.
Bridging the Gap: The Role of Ongoing Training and Coaching
Authors: Andersen Kurt
Published: February 2014

Did you know there is a major gap in the sales training process? This article shares the results of a survey that explores the gap, analyzes why it exists, and proposes strategic methods for addressing this issue.
The API Performance Contract
Authors: Sproull Robert , Waldo Jim
Published: February 2014

When you call functions in an API, you expect them to work correctly; sometimes this expectation is called a contract between the caller and the implementation. Callers also have performance expectations about these functions, and often the success of a software system depends on the API meeting these expectations. So there’s a performance contract as well as a correctness contract. The performance contract is usually implicit, often vague, and sometimes breached (by caller or implementation). How can this aspect of API design and documentation be improved?
Differential methylation in visceral adipose tissue of obese men discordant for metabolic disturbances
Authors: Guénard Frédéric , Tchernof André , Deshaies Yves , Pérusse Louis , Biron Simon , Lescelleur Odette , Biertho Laurent , Marceau Simon , Vohl Marie-Claude
Published: February 2014

Obesity is associated with an increased risk of Type 2 diabetes and cardiovascular diseases (CVD). The severely obese population is heterogeneous regarding CVD risk profile. Our objective was to identify metabolic pathways potentially associated with development of metabolic syndrome (MetS) through an analysis of overrepresented pathways from differentially methylated genes between severely obese men with (MetS+) and without (MetS−) the MetS. Genome-wide quantitative DNA methylation analysis in VAT of severely obese men was carried out using the Infinium HumanMethylation450 BeadChip. Differences in methylation levels between MetS+ ( n = 7) and MetS− ( n = 7) groups were tested. Overrepresented pathways from the list of differentially methylated genes were identified and visualized with the Ingenuity Pathway Analysis system. Differential methylation analysis between MetS+ and MetS− groups identified 8,578 methylation probes (3,258 annotated genes) with significant differences in methylation levels (false discovery rate-corrected DiffScore ≥ |13| ∼ P ≤ 0.05). Pathway analysis from differentially methylated genes identified 41 overrepresented ( P ≤ 0.05) pathways. The most overrepresented pathways were related to structural components of the cell membrane, inflammation and immunity and cell cycle regulation. This study provides potential targets associated with adipose tissue dysfunction and development of the MetS.
Silver Nanoparticles: Green Synthesis, Characterization, and Their Usage in Determination of Mercury Contamination in Seafoods
Authors: Ahmed Muhammad Ahad , Hasan Najmul , Mohiuddin Shaikh
Published: February 2014

We demonstrate that silver nanoparticles undergo an interaction with Hg2+ found in traces. The PEG-PVP-stabilized Ag nanoparticles were successfully synthesized via a reduction approach and characterized with surface plasmon resonance UV/Vis spectroscopy. By utilizing the redox reaction between Ag nanoparticles and Hg2+, and the resulted decrease in UV/Vis signal, we develop a colorimetric method for detection of Hg2+ ion. A linear and inversely proportional relationship was found between the absorbance intensity of the Ag nanoparticles and the concentration of Hg2+ ion over the range from 10 ppm to 1 ppm at absorption on 411 nm. The detection limit for Hg2+ ions in homogeneous aqueous solutions is estimated to be 1 ppm. This system shows excellent selectivity for Hg2+. The results found have potential implications in the development of new colorimetric sensors for easy and selective detection and monitoring of mercuric ions in aqueous solutions. The proposed method was successfully applied to quantify the amount of mercury in seafood.
Diagnostic Performance of Positron Emission Tomography/Computed Tomography Using Fluorine-18 Fluorodeoxyglucose in Detecting Locoregional Nodal Involvement in Patients with Anal Canal Cancer: A Systematic Review and Meta-Analysis
Authors: Caldarella Carmelo , Annunziata Salvatore , Treglia Giorgio , Sadeghi Ramin , Ayati Narjes , Giovanella Luca
Published: February 2014

Purpose. The diagnostic performance of positron emission tomography using18F-fluorodeoxyglucose (FDG-PET) in detecting nodal involvement in patients with anal canal cancer (ACC) has been investigated by several studies with conflicting results. The aim of our study is to systematically review and meta-analyze published data about this topic.Methods. A comprehensive computer literature search of PubMed/MEDLINE, Scopus, and Embase databases was carried out on July 10 to find relevant articles concerning the diagnostic performance of FDG-PET in detecting locoregional nodal involvement in patients with ACC. No language restriction was used. Pooled diagnostic performance on a lesion-based analysis was calculated.Results. Seven retrospective and five prospective studies have been reviewed. Six studies allowed assessing pooled sensitivity; five studies allowed assessing pooled specificity. Sensitivity and specificity values of FDG-PET/CT on a lesion-based analysis ranged from 31 to 100% and from 53 to 98%, with pooled estimates of 56% (95% CI: 45–67%) and 90% (95% CI: 86–93%), respectively.Conclusions. Our meta-analysis demonstrates that FDG-PET is a specific diagnostic tool in detecting locoregional lymph node involvement in patients with ACC. Low sensitivity is a major concern; however, higher sensitivity could be reached combining FDG-PET with MR scan.
A Fairness‐Based Access Control Scheme to Optimize IPTV Fast Channel Changing
Authors: Lai Junyu , Li James C. F. , Abdollahpouri Alireza , Zhang Jianhua , Lei Ming
Published: February 2014

IPTV services are typically featured with a longer channel changing delay compared to the conventional TV systems. The major contributor to this lies in the time spent on intraframe (I‐frame) acquisition during channel changing. Currently, most widely adopted fast channel changing (FCC) methods rely on promptly transmitting to the client (conducting the channel changing) a retained I‐frame of the targeted channel as a separate unicasting stream. However, this I‐frame acceleration mechanism has an inherent scalability problem due to the explosions of channel changing requests during commercial breaks. In this paper, we propose a fairness‐based admission control (FAC) scheme for the original I‐frame acceleration mechanism to enhance its scalability by decreasing the bandwidth demands. Based on the channel changing history of every client, the FAC scheme can intelligently decide whether or not to conduct the I‐frame acceleration for each channel change request. Comprehensive simulation experiments demonstrate the potential of our proposed FAC scheme to effectively optimize the scalability of the I‐frame acceleration mechanism, particularly in commercial breaks. Meanwhile, the FAC scheme only slightly increases the average channel changing delay by temporarily disabling FCC (i.e., I‐frame acceleration) for the clients who are addicted to frequent channel zapping.
Head and Neck Solitary Extramedullary Plasmacytoma
Authors: Khademi Bijan , Zandifar Zohreh , Mohammadianpanah Mohammad , Hamedi Sayed Hasan , Razzaghi Samira , Mahdavi Sareh , Moaddabshoar Leila
Published: February 2014

Introduction. This study aimed to report the characteristics and treatment outcome of 13 patients with solitary extramedullary plasmacytomas of the head and neck and analytical literature review. Materials and Methods. Nine patients (69%) were treated with gross surgical resection followed by radiotherapy, three (23%) were primarily treated with radiotherapy alone, and one (8%) was treated with surgery alone. Results. There were 3 women and 10 men with the median age of 52 years. Nasal cavity (46%) and paranasal sinuses (23%) were the most common primary sites. After a median follow-up of 28 months, 10 patients are alive and free of disease, one is alive with multiple myeloma, and two died of multiple myeloma. In the literature review the median age was 58 years and male/female ratio was 2.7. Sinonasal tract was the most common primary site. Ten-year local control and progression to multiple myeloma rates were 88% and 23%, respectively. The 5- and the 10-year overall survival rates were 71 and 69%, respectively. Conclusion. Radiation therapy with or without surgery is an effective treatment for patients with head and neck extramedullary plasmacytoma. However, long-term follow-up for detection of local recurrence and progression to multiple myeloma is essential.
Sodium Intake, Dietary Knowledge, and Illness Perceptions of Controlled and Uncontrolled Rural Hypertensive Patients
Authors: Kamran Aziz , Azadbakht Leila , Sharifirad Gholamreza , Mahaki Behzad , Sharghi Afshan
Published: February 2014

Introduction and Objectives. Nutritional knowledge of the patients is important in dietary adherence. This study aimed to determine the relationship between illness perceptions and nutritional knowledge with the amounts of sodium intake among rural hypertensive patients.Methods. In a cross-sectional study, 671 hypertensive patients were selected in a multistage random sampling from the rural areas of Ardabil city, Iran, in 2013. Data were collected using a questionnaire consisting of four sections and were analyzed using Pearson correlation and multiple linear regressions by SPSS-18.Results.The mean of sodium intake in the uncontrolled hypertensive patients was3599±258 mg/day and significantly greater than controlled group (2654±540 mg/day) (P<0.001). Knowledge and illness perceptions could predict 47.2% of the variation in sodium intake of uncontrolled group. A significant negative relationship was found between knowledge and illness perceptions of uncontrolled hypertensive patients with dietary sodium intake (r=-0.66,P<0.001andr=-0.65,P<0.001, resp.).Conclusion.Considering the fact that patients’ nutritional knowledge and illness perceptions could highly predict their sodium intake, the importance of paying more attention to improve patients’ information and perceptions about hypertension is undeniable, especially among the uncontrolled hypertensive patients.
Monotone Iterative Methods of Positive Solutions for Fractional Differential Equations Involving Derivatives
Authors: Zhang Xiaoping , Sun Yongping
Published: February 2014

This paper studies the existence and computing method of positive solutions for a class of nonlinear fractional differential equations involving derivatives with two‐point boundary conditions. By applying monotone iterative methods, the existence results of positive solutions and two iterative schemes approximating the solutions are established. The interesting point of our method is that the iterative scheme starts off with a known simple function or the zero function and the nonlinear term in the fractional differential equation is allowed to depend on the unknown function together with derivative terms. Two explicit numerical examples are given to illustrate the results.
Robust PID Steering Control in Parameter Space for Highly Automated Driving
Authors: Emirler Mümin Tolga , Uygan İsmail Meriç Can , Aksun Güvenç Bilin , Güvenç Levent
Published: February 2014

This paper is on the design of a parameter space based robust PID steering controller. This controller is used for automated steering in automated path following of a midsized sedan. Linear and nonlinear models of this midsized sedan are presented in the paper. Experimental results are used to validate the longitudinal and lateral dynamic models of this vehicle. This paper is on automated steering control and concentrates on the lateral direction of motion. The linear model is used to design a PID steering controller in parameter space that satisfies D-stability. The PID steering controller that is designed is used in a simulation study to illustrate the effectiveness of the proposed method. Simulation results for a circular trajectory and for a curved trajectory are presented and discussed in detail. This study is part of a larger research effort aimed at implementing highly automated driving in a midsized sedan.
Optimization of Process Parameters by Statistical Experimental Designs for the Production of Naringinase Enzyme by Marine Fungi
Authors: Shehata Abeer Nasr , Abd El Aty Abeer Abas
Published: February 2014

Naringinase has attracted a great deal of attention in recent years due to its hydrolytic activities which include the production of rhamnose and prunin and debittering of citrus fruit juices. Screening of fifteen marine-derived fungi, locally isolated from Ismalia, Egypt, for naringinase enzyme production, indicated thatAspergillus nigerwas the most promising. In solid state fermentation (SSF) of the agroindustrial waste, orange rind was used as a substrate containing naringin. Sequential optimization strategy, based on statistical experimental designs, was employed to enhance the production of the debittering naringinase enzyme. Effects of 19 variables were examined for their significance on naringinase production using Plackett-Burman factorial design. Significant parameters were further investigated using Taguchi’s (L1645) orthogonal array design. Based on statistical analysis (ANOVA), the optimal combinations of the major constituents of media for maximal naringinase production were evaluated as follows: 15 g orange rind waste, 30 mL moisture content, 1% grape fruit, 1% NaNO3, 0.5% KH2PO4, 5 mM MgSO4, 5 mM FeSO4, and the initial pH 7.5. The activity obtained was more than 3.14-fold the basal production medium.
Isolated Multiple Pigment Epithelial Detachments with Unknown Cause
Authors: Karatepe Hashas Arzu Seyhan , Göktas Altan , Atas Mustafa
Published: February 2014

There are many etiological factors that have led to the development of retinal pigment epithelial detachment (PED). In this paper, we have reported a patient with isolated multiple PEDs. Based on this fact, this paper aimed to give an overview of the causes of PEDs.
Numerical Prediction of Heat Transfer Characteristics of Nanofluids in a Minichannel Flow
Authors: Adil Arjumand , Gupta Sonam , Ghosh Pradyumna
Published: February 2014

CFD simulation of the heat transfer and pressure drop characteristics of different nanofluids in a minichannel flow has been explained using FLUENT version 6.3.26. Different nanofluids with nanoparticles of Al2O3, CuO, SiO2, and TiO2have been used in the simulation process. A comparison of the experimental and computational results has been made for the heat transfer and pressure drop characteristics for the case of Al2O3-water nanofluid for the laminar flow. Also, computations have been made by considering Brownian motion as well as without considering Brownian motion of the nanoparticles. After verification of the computational model with the experimental results for Al2O3-water nanofluid, the simulations were performed for the same experimental readings for different nanofluids in the laminar flow regime to find out the heat transfer and pressure drop characteristics.
Decreased Thioredoxin-1 and Increased HSP90 Expression in Skeletal Muscle in Subjects with Type 2 Diabetes or Impaired Glucose Tolerance
Authors: Venojärvi M. , Korkmaz A. , Aunola S. , Hällsten K. , Virtanen K. , Marniemi J. , Halonen J.-P. , Hänninen O. , Nuutila P. , Atalay M.
Published: February 2014

In diabetes, the endogenous defence systems are overwhelmed, causing various types of stress in tissues. In this study, newly diagnosed or diet-treated type 2 diabetics (T2D) (n=10) were compared with subjects with impaired glucose tolerance (IGT) (n=8). In both groups, at resting conditions, blood samples were drawn for assessing metabolic indices and skeletal muscle samples (m. vastus lateralis) were taken for the measurements of cellular defence markers: thioredoxin-1 (TRX-1) and stress proteins HSP72, HSP90. The protein level of TRX-1 was 36.1% lower (P=0.031) and HSP90 was 380% higher (P<0.001) in the T2D than in the IGT subjects, with no significant changes in HSP72. However, after the adjustment of both analyses with HOMA-IR only HSP90 difference remained significant. In conclusion, level of TRX-1 in skeletal muscle tissue was lower while that of HSP90 was higher in T2D than in IGT subjects. This may impair antioxidant defence and lead to disruptions of protein homoeostasis and redox regulation of cellular defences. Because HSP90 may be involved in sustaining functional insulin signalling pathway in type 2 diabetic muscles and higher HSP90 levels can be a consequence of type 2 diabetes, our results are potentially important for the diabetes research.
Adsorption Properties of Ni(II) by D301R Anion Exchange Resin
Authors: Xiuling Song , Huipu Du , Shijun Liu , Hui Qian
Published: February 2014

The adsorption of Ni(II) with D301R resin was investigated in this paper. The results showed that the saturated extent of adsorption Ni(II) by the resin was 84.3 mg/g. The equilibrium data of Ni(II) sorption was better described by Langmuir isotherm model (r2=0.994) while that of Ni(II) sorption also fitted in Freundlich isotherm model within the experimental concentration range. The amount of the constant (q0) of Ni(II) under 298 K in Langmuir model was 76.92 mg/g, which was close to the experimental results. The constant n was within 2–10 in Freundlich model; it was shown that adsorption of Ni(II) by the resin was easy to take place. The uptake kinetics followed the Lagergren pseudo-first-order rate equation (r2=0.9813). The particle diffusion controlled the adsorption process of Ni(II). The coefficient of the intraparticle diffusion increased with the increase of the pH values and the concentration of Ni(II) in aqueous solution. There was a drop of 20.1 cm−1for the bending vibration frequency of N–H bond. Results showed that the adsorption of Ni(II) by D301R anion exchange resin was the surface complexation through the infrared spectrum analysis.
Pregnancy-Associated Plasma Protein-A Levels and Coronary Angiographic Features in Acute Coronary Syndrome Patients
Authors: Shehata Mohamed
Published: February 2014

Background. Pregnancy-associated plasma protein-A (PAPP-A) is a biomarker of plaque rupture, associated with adverse cardiac events in acute coronary syndromes (ACSs) patients. Aim. To identify coronary angiographic (CA) features related to PAPP-A level elevation in ACSs patients. Methods. Forty ACSs patients were enrolled in this prospective cohort study (level of evidence: III-prognostic). Serum samples for PAPP-A quantitation were obtained upon coronary care unit admission. All patients underwent CA and coronary intervention within 6 hours of sampling. Results. Mean age of the study cohort was 57 ± 11 years, (males: 55%, n=22). Patients with ST-segment elevation myocardial infarction (35%, n=14) showed significantly higher serum PAPP-A level (11.8 ± 2 µg/mL), compared to non-ST-segment elevation myocardial infarction (15%, n=6) and unstable angina (50%, n=20) patients (11 ± 2.6 µg/mL and 8.7 ± 2.3 µg/mL, resp., P<0.001). Higher PAPP-A levels were significantly associated with complex culprit lesion morphology (11.8 ± 2 µg/mL for type C lesions, 9.7± 2.5 µg/mL and 7.3 ± 3.5 µg/mL for type B and type A lesions, resp., P<0.001), while no relationship to number of diseased coronaries. Conclusion. Higher PAPP-A levels in ACSs patients are associated with unfavorable coronary anatomy and complex angiographic plaque features.
Management of Tonsillar Lipoma: Is Tonsillectomy Essential?
Authors: Kanotra Sohit P. , Davies Joel
Published: February 2014

Tonsillar lipomas are rare benign tumors, with only a limited number of cases reported in the literature. Excision of the lipoma along with tonsillectomy has been proposed as the usual treatment option. We report a case of tonsillar lipoma which was managed by excision of the lesion without the need for a tonsillectomy. No recurrence was reported at a 2-year followup. A worldwide literature review was done to better define the clinical and histopathological features of these lesions. The authors propose that routine tonsillectomy is not required for these benign lesions and that simple excision of the stalk of the lipoma is sufficient.
Role of Polysaccharides in Complex Mixtures with Soy Protein Hydrolysate on Foaming Properties Studied by Response Surface Methodology
Authors: Martínez Karina D. , Pilosof Ana M. R.
Published: February 2014

The complex mixture studied, a hydrolyzed soy protein (HSP), κ-carrageenan (κC), and an hydroxypropyl methylcellulose (HPMC), could be used as a foaming agent under refrigeration or heating conditions because of the presence of one polysaccharide (HPMC) that gels on heating and another (κC) that gels on cooling. The objective of this work was to study the role of these polysaccharides on foaming properties by whipping methods at heating conditions. For this purpose, response surface methodology was used to optimize the mixed product in foamed food systems. The obtained results showed that the combination of E4M, κC, and HSP is an adequate strategy to generate good foam capacity and stability at heating conditions. The huge stability increase of foams at heating conditions was ascribed to combined effect of polysaccharides: gelling property of E4M and the viscozieng character imparted by κC to continuous phase of foaming.
Explicit Finite Difference Methods for the Delay Pseudoparabolic Equations
Authors: Amirali I. , Amiraliyev G. M. , Cakir M. , Cimen E.
Published: February 2014

Finite difference technique is applied to numerical solution of the initial-boundary value problem for the semilinear delay Sobolev or pseudoparabolic equation. By the method of integral identities two-level difference scheme is constructed. For the time integration the implicit rule is being used. Based on the method of energy estimates the fully discrete scheme is shown to be absolutely stable and convergent of order two in space and of order one in time. The error estimates are obtained in the discrete norm. Some numerical results confirming the expected behavior of the method are shown.
Prediction of Frequency for Simulation of Asphalt Mix Fatigue Tests Using MARS and ANN
Authors: Ghanizadeh Ali Reza , Fakhri Mansour
Published: February 2014

Fatigue life of asphalt mixes in laboratory tests is commonly determined by applying a sinusoidal or haversine waveform with specific frequency. The pavement structure and loading conditions affect the shape and the frequency of tensile response pulses at the bottom of asphalt layer. This paper introduces two methods for predicting the loading frequency in laboratory asphalt fatigue tests for better simulation of field conditions. Five thousand (5000) four-layered pavement sections were analyzed and stress and strain response pulses in both longitudinal and transverse directions was determined. After fitting the haversine function to the response pulses by the concept of equal-energy pulse, the effective length of the response pulses were determined. Two methods including Multivariate Adaptive Regression Splines (MARS) and Artificial Neural Network (ANN) methods were then employed to predict the effective length (i.e., frequency) of tensile stress and strain pulses in longitudinal and transverse directions based on haversine waveform. It is indicated that, under controlled stress and strain modes, both methods (MARS and ANN) are capable of predicting the frequency of loading in HMA fatigue tests with very good accuracy. The accuracy of ANN method is, however, more than MARS method. It is furthermore shown that the results of the present study can be generalized to sinusoidal waveform by a simple equation.