bluuebunny/crossref_metadata_2025 huggingface dataset:
Synchronous papillary cystadenocarcinoma of ovary and squamous cell carcinoma of lower vagina: first report of an unusual chance occurrence
Authors: Shekhar Shashank , Thakur Sita , Singh Kamal , Chander Bal
Published: January 2013

Synchronously occurring primary gynecological malignancies are rare, and most commonly reported synchronous female genital malignancies are ovarian and endometrial. It is postulated that the extended Mullerian system, comprising the ovarian epithelium, fallopian tube, uterine corpus and cervix, may respond as a single morphological unit to a carcinogenic process, thus producing primary tumours at above-mentioned sites in varying combinations.  We are reporting for the first time, an unusual occurrence of synchronous papillary serous cystadenocarcinoma of the ovary and sqaumous cell carcinoma of lower vagina. Clinical implications of this case along with the multicentric concept of tumourigenesis and diagnosis of synchronous female genital malignancies are briefly discussed. Index case is probably a chance occurrence, as it cannot be explained by the current concepts of muticentric tumourogenesis in the female genital tract. Nonetheless, further research is warranted to explain simultaneous tumourogenesis in embryologically different tissues.
Shock following a cat scratch
Authors: Yamamoto Umpei , Kunita Mutsumi , Mohri Masahiro
Published: January 2013

A 49-year-old man with fever, pain in both legs, purpuras and cyanosis was admitted to hospital. He was a heavy drinker, but did not have diabetes or other immunosuppressive disease. On admission, he was in shock, with haematological findings suggestive of disseminated intravascular coagulation, and liver and kidney failure. The presence of a scratch wound on his face caused by a cat, and linear, Gram-negative rods phagocytosed by polynuclear leucocytes on peripheral blood smear suggestedCapnocytophaga canimorsusinfection. On day 1, antibiotics (ampicillin/sulbactam) and catecholamines were initiated. The patient required haemodialysis three times per week for 3 weeks. His toes became necrotic but improved and amputation was not necessary. On day 52, he was discharged from hospital with only mild sensory impairment of the legs.
Autologous tenocyte implantation, a novel treatment for partial-thickness rotator cuff tear and tendinopathy in an elite athlete
Authors: Wang Allan W , Bauer Stefan , Goonatillake Matthew , Breidahl William , Zheng Ming-Hao
Published: January 2013

Tendinopathy and small partial-thickness tears of the rotator cuff tendon are common presentations in sports medicine. No promising treatment has yet been established. Corticosteroid injections may improve symptoms in the short term but do not primarily treat the tendon pathology. Ultrasound-guided autologous tenocyte implantation (ATI) is a novel bioengineered treatment approach for treating tendinopathy. We report the first clinical case of ATI in a 20-year-old elite gymnast with a rotator cuff tendon injury. The patient presented with 12 months of increasing pain during gymnastics being unable to perform most skills. At 1 year after ATI the patient reported substantial improvement of clinical symptoms. Pretreatment and follow-up MRIs were reported and scored independently by two experienced musculoskeletal radiologists. Tendinopathy was improved and the partial-thickness tear healed on 3 T MRI. The patient was able to return to national-level competition.
Aortic arch variant presenting as an acute ST elevation myocardial infarction
Authors: Alirhayim Zaid , Qureshi Waqas , Shafiq Ali , Hassan Syed
Published: January 2013

A woman in her 40s presented to our institution with a first episode of sudden-onset right-sided chest pain. Initially, her ECG revealed ST segment elevation in leads V1–V3 and cardiac biomarkers were elevated with a troponin I (TnI) 5 µg/l. Her cardiac risk factors included type II diabetes mellitus and a history of hypertension. Intravenous heparin was initiated and emergent cardiac catheterisation revealed non-obstructive coronary artery disease. A two-dimensional echocardiogram confirmed hypokinesis of the anterior wall. A CT thorax demonstrated a rare anatomical variant of the aortic arch with an aberrant right subclavian artery. This is a rare case of an aortic arch anomaly presenting as a myocardial infarction.
Parkinsonism can be cured
Authors: Lobo Ronstan , Fraser Alexander , Kiely Patrick , Boers Peter
Published: January 2013

This case describes a woman with a history of rheumatoid arthritis with secondary vasculitic skin ulcers, Sicca syndrome and idiopathic Parkinson's disease that was diagnosed by a neurologist in 2005. The patient's parkinsonian symptoms were difficult to control, despite the use of antiparkinsonian medications. During a regular clinical review in 2011, the patient's rheumatologist had prescribed cyclophosphamide infusions to help with the vasculitic skin ulcers. Over the following 2 months, the patient's parkinsonian symptoms completely resolved.
If it is not healing, do worry about it!
Authors: Schade Alexander Thomas , Raymond Antony Claud , Amirfeyz Rouin
Published: January 2013

We present the case of a 44-year-old patient who crushed her ring finger in a door 4 months earlier. She was treated in the community for her chronic fingertip wound/pyogenic granuloma. As the lesion was not healing with regular wound management she was eventually referred to secondary care for an opinion. She underwent immediate excisional biopsy with safe margins for tissue diagnosis and had histological confirmation of an advanced malignant melanoma. The staging head, neck, thorax, abdomen and pelvic CT showed lymph node enlargement and widespread metastatic lesions. Our case shows how if hand lesions are not resolved following trauma, the patient needs to be assessed for unusual pathologies and, if necessary, or in doubt, referred to the specialists.
Cross-sectional study of prescribing errors in patients admitted to nine hospitals across North West England
Authors: Seden Kay , Kirkham Jamie J , Kennedy Tom , Lloyd Michael , James Sally , Mcmanus Aine , Ritchings Andrew , Simpson Jennifer , Thornton Dave , Gill Andrea , Coleman Carolyn , Thorpe Bethan , Khoo Saye H
Published: January 2013

Objective

To evaluate the prevalence, type and severity of prescribing errors observed between grades of prescriber, ward area, admission or discharge and type of medication prescribed.

Design

Ward-based clinical pharmacists prospectively documented prescribing errors at the point of clinically checking admission or discharge prescriptions. Error categories and severities were assigned at the point of data collection, and verified independently by the study team.

Setting

Prospective study of nine diverse National Health Service hospitals in North West England, including teaching hospitals, district hospitals and specialist services for paediatrics, women and mental health.

Results

Of 4238 prescriptions evaluated, one or more error was observed in 1857 (43.8%) prescriptions, with a total of 3011 errors observed. Of these, 1264 (41.9%) were minor, 1629 (54.1%) were significant, 109 (3.6%) were serious and 9 (0.30%) were potentially life threatening. The majority of errors considered to be potentially lethal (n=9) were dosing errors (n=8), mostly relating to overdose (n=7). The rate of error was not significantly different between newly qualified doctors compared with junior, middle grade or senior doctors. Multivariable analyses revealed the strongest predictor of error was the number of items on a prescription (risk of error increased 14% for each additional item). We observed a high rate of error from medication omission, particularly among patients admitted acutely into hospital. Electronic prescribing systems could potentially have prevented up to a quarter of (but not all) errors.

Conclusions

In contrast to other studies, prescriber experience did not impact on overall error rate (although there were qualitative differences in error category). Given that multiple drug therapies are now the norm for many medical conditions, health systems should introduce and retain safeguards which detect and prevent error, in addition to continuing training and education, and migration to electronic prescribing systems.
Consequences of the increasing prevalence of the poisonousLagocephalus sceleratusin southern Turkey
Authors: Beköz Alev Banu , Beköz Sera , Yilmaz Elanur , Tüzün Suna , Beköz Üner
Published: January 2013

Background

The increasing Indo-Pacific migration has affected the biodiversity of the Mediterranean Sea, and the prevalence of the puffer fish (Lagocephalus sceleratus), a well-known poisonous migrant, is increasing. The fish, which contains tetrodotoxin, is lethally poisonous when consumed. As its population increases it becomes more available in the markets of southern Turkey, but local people seem to be unaware of the danger. Probably because of the depressed stocks of the surrounding waters and demand on affordable seafood, local anglers are catching the fish. The situation constitutes an alert for the local emergency medicine organisation and is a public health issue.

Methods

Local fishermen, fish sellers/dealers/brokers, buyers and emergency department physicians were interviewed about the fishery and consumption facts of the puffer fish in the region, the number of cases reported in the regional state run hospitals and the 112 Emergency Medical Response Service, and the knowledge and practice of the doctors in the emergency departments.

Results and conclusions

General health organisations are unprepared for the serious health hazards caused by this fish, including fatalities. Health workers should have sufficient knowledge regarding the clinical manifestations, complications and management of puffer fish poisoning. Official authorities should make the public aware of the potential risk of consuming puffer fish.
A corneal cat‐astrophe?
Authors: Williams David
Published: January 2013

Articles in this series give readers the opportunity to consider and contribute to discussion of some of the ethical dilemmas that can arise in veterinary practice. Each month, a case scenario is presented, followed by discussion of some of the issues involved. In addition, a possible way forward is suggested; however, there is rarely a cut‐and‐dried answer in such cases, and readers may wish to suggest an alternative approach. This month's dilemma, ‘A corneal cat‐astrophe?’, is presented and discussed by David Williams. Readers with comments to contribute are invited to send them as soon as possible, so that they can be considered for publication in the next issue. Discussion of the dilemma ‘Are you positive? The fate of a shelter cat’, which was published in the November/December 2012 issue of In Practice, appears on page 47.

The series is being coordinated by Siobhan Mullan, of the University of Bristol. It is hoped it will provide a framework that will help practices find solutions when facing similar dilemmas.
Remote chemical injection: darting in practice
Authors: Cracknell Jonathan
Published: January 2013

Remote chemical injection (RCI) is colloquially known as darting but can also include the use of pole syringes. Most commonly associated with zoo and wildlife veterinarians, these techniques are becoming more commonly applied by veterinary colleagues in the management of stray or aggressive small or large animals, as well as in the circus, television and movie industries. The use of remote techniques is not limited to the induction of anaesthesia; they can be used in the administration of any therapeutic agent that can be given via the intramuscular route. This article reviews the types of systems available, the use and maintenance of these systems and considerations when darting. It also looks at the legislative issues surrounding these useful therapeutic modalities.
Use of wound soaker catheters in pain management
Authors: Armitage‐Chan Elizabeth
Published: January 2013

Wound soaker catheters provide a useful method for administering local anaesthetic direct to the wound site, avoiding the problems that come with regular administration, such as a limited duration of action or lack of available nerve blocks. This article describes the use of wound soaker catheters, explains their advantages and includes some practical tips for the clinician.
Does the HM mechanism work in string theory?
Authors: Sepehri Alireza , Shoorvazi Somayyeh , Zomorrodian Mohammad Ebrahim
Published: January 2013

The correspondence principle offers a unique opportunity to test the Horowitz and Maldacena mechanism at the correspondence point “the centre of mass energies around (Ms/(gs)2)”. First by using the Horowitz and Maldacena proposal, the black hole final state for closed strings is studied and the entropy of these states is calculated. Then, to consider the closed string states, a copy of the original Hilbert space is constructed with a set of creation–annihilation operators that have the same commutation properties as the original ones. The total Hilbert space is the tensor product of the two spaces Hright ⊗ Hleft, where in this case Hleft/right denote the physical quantum state space of the closed string. It is shown that closed string states can be represented by a maximally entangled two-mode squeezed state of the left and right spaces of closed string. Also, the entropy for these string states is calculated. It is found that black hole entropy matches the closed string entropy at transition point. This means that our result is consistent with correspondence principle and thus HM mechanism in string theory works. Consequently the unitarity of the black hole in string theory can be reconciled. However Gottesman and Preskill point out that, in this scenario, departures from unitarity can arise due to interactions between the collapsing body and the infalling Hawking radiation inside the event horizon and information can be lost. By extending the Gottesman and Preskill method to string theory, the amount of information transformation from the matter to the state of outgoing Hagedorn radiation for closed strings is obtained. It is observed that information is lost for closed strings.
Two-dimensional Duffin–Kemmer–Petiau oscillator under an external magnetic field
Authors: Boumali Abdelmalek , Chetouani Lyazid , Hassanabadi Hassan
Published: January 2013

The eigensolutions of massive spin-0 and spin-1 particles of a Dirac oscillator in an external magnetic field, both in the commutative and noncommutative space, are found by using the Duffin–Kemmer–Petiau equation. The solutions in both cases are obtained using the parametric generalization of the Nikiforov–Uvarov method.
A SEARCHER VERSUS HIDER GAME WITH INCOMPLETE INFORMATION ABOUT SEARCH RESOURCES
Authors: GARNAEV ANDREY , FOKKINK ROBBERT
Published: January 2013

We introduce a search game in which a hider has partial information about a searcher's resource. The hider can be a terrorist trying to hide and the searcher can be special forces trying to catch him. The terrorist does not know the number of forces involved in the search but just its distribution. We model this situation by a noncooperative game. In a related setup, which is motivated by wireless networks applications, the terrorist inserts a malicious node in a network, reducing network connectivity and thereby undermining its security. Meanwhile, the network operator applies appropriate measures to detect malicious nodes and maintain network performance. We investigate how the information about the total search resources that are available to the hider can influence the behavior of both players. For the case, where the distribution has two mass points, we prove that the game has a unique equilibrium and moreover, we describe explicitly this equilibrium, its structure and some other properties.
FORM INVARIANCE SYMMETRY GENERATES A LARGE SET OF FRW COSMOLOGIES
Authors: CHIMENTO LUIS P. , RICHARTE MARTÍN G. , SÁNCHEZ IVÁN E.
Published: January 2013

We show that Einstein's field equations for spatially flat Friedmann–Robertson–Walker (FRW) spacetimes have a form invariance symmetry (FIS) realized by the form invariance transformations (FIT) which are indeed generated by an invertible function of the source energy density. These transformations act on the Hubble expansion rate, the energy density and pressure of the cosmic fluid; likewise such transformations are endowed with a Lie group structure. Each representation of this group is associated with a particular fluid and consequently a determined cosmology, so that, the FIS defines a set of equivalent cosmological models. We focus our seek in the FIT generated by a linear function because it provides a natural framework to express the duality and also produces large sets of cosmologies, starting from a seed one, in several contexts as for instance in the cases of a perfect fluid source and a scalar field driven by a potential depending linearly on the scalar field kinetic energy density.
NEUTRINO ASTRONOMY AT THE SOUTH POLE
Authors: KARLE ALBRECHT
Published: January 2013

The origin of highest energy cosmic rays remains unresolved. High-energy neutrinos may provide the clues to fundamental phenomena such as the origin of cosmic rays or dark matter in the Universe. The IceCube Neutrino Observatory, a km scale neutrino detector, has come into full operation in 2011. At the highest energy levels, prototypes of a new experiment, the Askaryan Radio Array, have been deployed and are being tested. We report on the status, first results and prospects of the experimental neutrino searches under way and planned at the South Pole.
CHERENKOV RADIATION INDUCED BY COSMOGENIC NEUTRINOS IN NEAR-FIELD
Authors: HU CHIA-YU , CHEN CHIH-CHING , CHEN PISIN
Published: January 2013

The radio technique of cosmogenic neutrino detection, which relies on the Cherenkov signals coherently emitted from the particle showers in dense medium, has now become a mature field. We present an alternative approach to calculate such Cherenkov pulse by a numerical code based on the finite difference time-domain (FDTD) method that does not rely on the far-field approximation. We show that for a shower elongated by the LPM (Landau-Pomeranchuk-Migdal) effect and thus with a multi-peak structure, the generated Cherenkov signal will always be a bipolar and asymmetric waveform in the near-field regime regardless of the specific variations of the multi-peak structure, which makes it a generic and distinctive feature. This should provide an important characteristic signature for the identification of ultra-high energy cosmogenic neutrinos.
NODAL AND MULTIPLE SOLUTIONS FOR NONLINEAR PERIODIC PROBLEMS WITH COMPETING NONLINEARITIES
Authors: AIZICOVICI SERGIU , PAPAGEORGIOU NIKOLAOS S. , STAICU VASILE
Published: January 2013

We consider a nonlinear periodic problem drive driven by a nonhomogeneous differential operator which incorporates as a special case the scalar p-Laplacian, and a reaction which exhibits the competition of concave and convex terms. Using variational methods based on critical point theory, together with suitable truncation techniques and Morse theory (critical groups), we establish the existence of five nontrivial solutions, two positive, two negative and the fifth nodal (sign-changing). In the process, we also prove some auxiliary results of independent interest.
EXTENSIONS OF VECTOR BUNDLES WITH APPLICATION TO NOETHER–LEFSCHETZ THEOREMS
Authors: RAVINDRA G. V. , TRIPATHI AMIT
Published: January 2013

Given a smooth, projective variety Y over an algebraically closed field of characteristic zero, and a smooth, ample hyperplane section X ⊂ Y, we study the question of when a bundle E on X, extends to a bundle [Formula: see text] on a Zariski open set U ⊂ Y containing X. The main ingredients used are explicit descriptions of various obstruction classes in the deformation theory of bundles, together with Grothendieck–Lefschetz theory. As a consequence, we prove a Noether–Lefschetz theorem for higher rank bundles, which recovers and unifies the Noether–Lefschetz theorems of Joshi and Ravindra–Srinivas.
THE FINITISTIC DIMENSION CONJECTURE AND RELATIVELY PROJECTIVE MODULES
Authors: XI CHANGCHANG , XU DENGMING
Published: January 2013

The famous finitistic dimension conjecture says that every finite-dimensional 𝕂-algebra over a field 𝕂 should have finite finitistic dimension. This conjecture is equivalent to the following statement: If B is a subalgebra of a finite-dimensional 𝕂-algebra A such that the radical of B is a left ideal in A, and if A has finite finitistic dimension, then B has finite finitistic dimension. In the paper, we shall work with a more general setting of Artin algebras. Let B be a subalgebra of an Artin algebra A such that the radical of B is a left ideal in A. (1) If the category of all finitely generated (A, B)-projective A-modules is closed under taking A-syzygies, then fin.dim (B) ≤ fin.dim (A) + fin.dim (BA) + 3, where fin.dim (A) denotes the finitistic dimension of A, and where fin.dim (BA) stands for the supremum of the projective dimensions of those direct summands of BA that have finite projective dimension. (2) If the extension B ⊆ A is n-hereditary for a non-negative integer n, then gl.dim (A) ≤ gl.dim (B) + n. Moreover, we show that the finitistic dimension of the trivially twisted extension of two algebras of finite finitistic dimension is again finite. Also, a new formulation of the finitistic dimension conjecture in terms of relative homological dimension is given. Our approach in this paper is completely different from the one in our earlier papers.
WELL-POSEDNESS FOR A FAMILY OF PERTURBATIONS OF THE KdV EQUATION IN PERIODIC SOBOLEV SPACES OF NEGATIVE ORDER
Authors: PAREDES XAVIER CARVAJAL , PASTRAN RICARDO A.
Published: January 2013

We establish local well-posedness in Sobolev spaces Hs(𝕋), with s ≥ -1/2, for the initial value problem issues of the equation [Formula: see text] where η > 0, (Lu)∧(k) = -Φ(k)û(k), k ∈ ℤ and Φ ∈ ℝ is bounded above. Particular cases of this problem are the Korteweg–de Vries–Burgers equation for Φ(k) = -k2, the derivative Korteweg–de Vries–Kuramoto–Sivashinsky equation for Φ(k) = k2- k4, and the Ostrovsky–Stepanyams–Tsimring equation for Φ(k) = |k| - |k|3.
SEPARATING PARKINSONIAN PATIENTS FROM NORMAL PERSONS USING HANDWRITING FEATURES
Authors: SARBAZ YASHAR , TOWHIDKHAH FARZAD , MOSAVARI VAHAB , JANANI AZIN , SOLTANZADEH AKBAR
Published: January 2013

Parkinson's disease (PD) is a widespread progressive neural degenerative disease. Patients encounter problems in carrying out ordinary voluntary movements such as gaiting and writing. Effects of tremor, rigidity, and bradykinesia are seen in writing. Since the diagnosis of PD is based on the presence of cardinal symptoms, therefore voluntary movements like writing could be helpful as an indicator in this process. Handwriting analysis can be a suitable method to separate patients from normal individuals. We recorded handwriting data from 17 normal and 13 PD subjects, and then used mathematical analysis in order to extract proper features. At the end of the study, we used these selected features in a classifier. We achieved 93.89% accuracy in the test phase. Hence, this tool may be aid in the diagnosing of both PD and suspected PD individuals in the early stages of the disease.
An Ontology-Based Collaborative Inter-Organisational Knowledge Management Network (CIK-NET)
Authors: Leung Nelson K. Y. , Lau Sim Kim , Tsang Nicole
Published: January 2013

Ontologies are widely used to represent knowledge explicitly but it is impractical to expect all individuals and organisations to agree on using one or a small subset of ontologies. The adoption of multiple ontologies causes ontology mismatches which make their inherent vocabularies and relationships become inconsistent, resulting in difficulty for one system to understand and reuse these ontologies. To achieve knowledge sharing and reuse, ontology mediation is required to reconcile mismatches between heterogeneous ontologies. In this paper, we investigate the application of ontology in knowledge management (KM). Many KM approaches have been developed with the purpose of managing organisational knowledge. However, these approaches only focus on managing intra-organisational knowledge, which is inadequate in current business environment because users are often required to access inter-organisational knowledge to complete their tasks. These approaches also fail to collaborate with each other as their designs are based on their own business and KM requirement in managing organisational knowledge. We argue that ontology and its mediation methods can be used to overcome limitation of non-collaborative problem in which individual organisation is unable to reuse inter-organisational knowledge. An ontology-based inter-organisational KM network is therefore proposed to allow organisations accessing and retrieving inter-organisational knowledge of common domain.
REMOTE IMPLEMENTATION OF AN UNKNOWN SINGLE-QUBIT OPERATION BY DIFFERENT DIMENSIONAL QUANTUM CHANNEL
Authors: ZHAN YOU-BANG , MA PENG-CHENG , ZHANG QUN-YONG
Published: January 2013

We present two novel protocols for remote implementation of an unknown single-qubit operation with an EPR pair and a high-dimensional entangled state as the quantum channel, without and with quantum control. The main strategy of the protocols is teleportation of an unknown single-qubit operation, which consists of an usual teleportation of an arbitrary single-qubit state, nonsymmetric basis measurement, and corresponding local transformation. It is shown that the teleportation of the quantum operation can be implemented with unit successful probability.
xTune
Authors: Kim Minyoung , Stehr Mark-Oliver , Talcott Carolyn , Dutt Nikil , Venkatasubramanian Nalini
Published: January 2013

Resource-limited mobile embedded systems can benefit greatly from dynamic adaptation of system parameters. We propose a novel approach that employs iterative tuning using lightweight formal verification at runtime with feedback for dynamic adaptation. One objective of this approach is to enable trade-off analysis across multiple layers (e.g., application, middleware, OS) and predict the possible property violations as the system evolves dynamically over time. Specifically, an executable formal specification is developed for each layer of the mobile system under consideration. The formal specification is then analyzed using statistical property checking and statistical quantitative analysis, to determine the impact of various resource management policies for achieving desired timing/QoS properties. Integration of formal analysis with dynamic behavior from system execution results in a feedback loop that enables model refinement and further optimization of policies and parameters. We demonstrate the applicability of this approach to the adaptive provisioning of resource-limited distributed real-time systems using a mobile multimedia case study.
Implementing constrained cyber-physical systems with IEC 61499
Authors: Yoong Li Hsien , Roop Partha S. , Salcic Zoran
Published: January 2013

Cyber-physical systems (CPS) are integrations of computation and control with sensing and actuation of the physical environment. Typically, such systems consist of embedded computers that monitor and control physical processes in a feedback loop. While modern electronic systems are increasingly characterized as CPS, their design and synthesis still rely on traditional methods, which lack systematic and automated techniques for accomplishment.

Recently, IEC 61499 has been proposed as a standard for designing industrial process-control and measurement systems. It prescribes a component-based approach for developing industrial automation software using function blocks. Executable code can then be automatically generated and simulated from these function blocks. This bodes well for designers of CPS, who are more likely to be experts in specific industrial domains, rather than in computer science. The intuitive graphical nature and automatic code synthesis of IEC 61499 programs will alleviate the programming burden of industrial engineers, while ensuring more reliable software. While software synthesis from IEC 61499 programs is not new, the generation of efficient code from them has been wanting. This has made it difficult for function blocks to be used in software development for resource-constrained embedded controllers commonly employed in CPS. To address this, we present an approach that can generate very efficient code from function block descriptions. Experimental results from a benchmark suite shows that our approach produces substantially faster and smaller code compared to existing techniques.
Modeling towards incremental early analyzability of networked avionics systems using virtual integration
Authors: Nam Min-Young , Kang Kyungtae , Pellizzoni Rodolfo , Park Kyung-Joon , Kim Jung-Eun , Sha Lui
Published: January 2013

With the advance of hardware technology, more features are incrementally added to already existing networked systems. Avionics has a stronger tendency to use preexisting applications due to its complexity and scale. As resource sharing becomes intense among the network and the computing modules, it has become a difficult task for the system designer to make confident architectural decisions even for incremental changes. Providing a tailored environment to model and analyze incremental changes requires a combination of software tools and hardware support. We have built a virtual integration tool called ASIIST which can provide a worst-case end-to-end latency of data that is sent through a network and the internal bus architecture of the end-systems. Also, we have devised a new real-time switching algorithm which guarantees the worst-case network delay of preexisting network traffic under feasible conditions. With the real-time switch support, ASIIST can provide an early modularized analysis of the end-to-end latency to make architectural design choices and incremental changes easier for the user.
Optimization of task allocation and priority assignment in hard real-time distributed systems
Authors: Zhu Qi , Zeng Haibo , Zheng Wei , Natale Marco DI , Sangiovanni-Vincentelli Alberto
Published: January 2013

The complexity and physical distribution of modern active safety, chassis, and powertrain automotive applications requires the use of distributed architectures. Complex functions designed as networks of function blocks exchanging signal information are deployed onto the physical HW and implemented in a SW architecture consisting of a set of tasks and messages. The typical configuration features priority-based scheduling of tasks and messages and imposes end-to-end deadlines. In this work, we present and compare formulations and procedures for the optimization of the task allocation, the signal to message mapping, and the assignment of priorities to tasks and messages in order to meet end-to-end deadline constraints and minimize latencies. Our formulations leverage worst-case response time analysis within a mixed integer linear optimization framework and are compared for performance against a simulated annealing implementation. The methods are applied for evaluation to an automotive case study of complexity comparable to industrial design problems.
Robust image processing for an omnidirectional camera-based smart car door
Authors: Scharfenberger Christian , Chakraborty Samarajiit , Färber Georg
Published: January 2013

Over the last decade, there has been an increasing emphasis on driver-assistance systems for the automotive domain. In this article, we report our work on designing a camera-based surveillance system embedded in a “smart” car door. Such a camera is used to monitor the ambient environment outside the car, for instance, the presence of obstacles such as approaching cars or cyclists who might collide with the car door if opened—and automatically control the car door operations. This is an enhancement to the currently available side-view mirrors that the driver/passenger checks before opening the car door. The focus of this article is on fast and robust image processing algorithms specifically targeting such a smart car door system. The requirement is to quickly detect traffic objects of interest from grayscale images captured by omnidirectional cameras. While known algorithms for object extraction from the image processing literature rely on color information and are sensitive to shadows and illumination changes, our proposed algorithms are highly robust, can operate on grayscale images (color images are not available in our setup), and output results in real time. We present a number of experimental results based on image sequences captured from real-life traffic scenarios to demonstrate the applicability of our algorithm.
Two-Part Models Capture the Impact of Gain on Pointing Performance
Authors: Shoemaker Garth , Tsukitani Takayuki , Kitamura Yoshifumi , Booth Kellogg S.
Published: January 2013

We establish that two-part models of pointing performance (Welford’s model) describe pointing on a computer display significantly better than traditional one-part models (Fitts’s Law). We explore the space of pointing models and describe how independent contributions of movement amplitude and target width to pointing time can be captured in a parameter
k
. Through a reanalysis of data from related work we demonstrate that one-part formulations are fragile in describing pointing performance, and that this fragility is present for various devices and techniques. We show that this same data can be significantly better described using two-part models. Finally, we demonstrate through further analysis of previous work and new experimental data that
k
increases linearly with gain. Our primary contribution is the demonstration that Fitts’s Law is more limited in applicability than previously appreciated, and that more robust models, such as Welford’s formulation, should be adopted in many cases of practical interest.
Enriching Archaeological Parks with Contextual Sounds and Mobile Technology
Authors: Ardito Carmelo , Costabile Maria F. , De Angeli Antonella , Lanzilotti Rosa
Published: January 2013

The importance of cultural heritage in forging a sense of identity is becoming increasingly evident. Information and communication technologies have a great potential to promote a greater awareness and appreciation of cultural heritage. This article presents some findings on how mobile technology can be used to foster a better understanding of an archaeological site by reconstructing the ancient environment and life. Children aged 11--13 years old are the target of our research. To motivate and engage them, a pervasive educational game has been developed and implemented in
Explore!
, a system aimed at supporting children exploring sites of cultural interest. Special attention has been devoted to the design of a soundscape that may improve players’ navigation in degraded physical environments and enrich their overall experience. A field study indicated that children judged their experience both useful and entertaining: not only did they enjoy playing the game, but they also learned historical notions and facts related to ancient Roman life. Contextual sounds were found to have a facilitating effect on space navigation, reducing the need for map reading and improving spatial orientation. This work provides insights into the design of educational games for use with cultural heritage and a model to enrich historical sites through the creation of soundscapes which can help visitors to navigate a site and feel its historical atmosphere.
Physical Activity Motivating Games
Authors: Berkovsky Shlomo , Freyne Jill , Coombe Mac
Published: January 2013

People’s daily lives have become increasingly sedentary, with extended periods of time being spent in front of a host of electronic screens for learning, work, and entertainment. We present research into the use of an adaptive persuasive technology, which introduces bursts of physical activity into a traditionally sedentary activity: computer game playing. Our game design approach leverages the playfulness and addictive nature of computer games to motivate players to engage in mild physical activity. The design allows players to gain virtual in-game rewards in return for performing real physical activity captured by sensory devices. This article presents a two-stage analysis of the activity-motivating game design approach applied to a prototype game. Initially, we detail the overall acceptance of active games discovered when trialing the technology with 135 young players. Results showed that players performed more activity without negatively affecting their perceived enjoyment of the playing experience. The analysis did discover, however, a lack of balance between the amounts of physical activity carried out by players with various gaming skills, which prompted a subsequent investigation into adaptive techniques for balancing the amount of physical activity performed by players. An evaluation of additional 90 players showed that adaptive techniques successfully overcame the gaming skills dependence and achieved more balanced activity levels. Overall, this work positions activity-motivating games as an approach that can potentially change the way players interact with computer games and lead to healthier lifestyles.
Natural and Flexible Error Recovery for Generated Modular Language Environments
Authors: de Jonge Maartje , Kats Lennart C. L. , Visser Eelco , Söderberg Emma
Published: January 2013

Integrated Development Environments (IDEs) increase programmer productivity, providing rapid, interactive feedback based on the syntax and semantics of a language. Unlike conventional parsing algorithms, scannerless generalized-LR parsing supports the full set of context-free grammars, which is closed under composition, and hence can parse languages composed from separate grammar modules. To apply this algorithm in an interactive environment, this article introduces a novel error recovery mechanism. Our approach is language independent, and relies on automatic derivation of recovery rules from grammars. By taking layout information into consideration it can efficiently suggest natural recovery suggestions.
On the Termination of Integer Loops
Authors: Ben-Amram Amir M. , Genaim Samir , Masud Abu Naser
Published: January 2013

In this article we study the decidability of termination of several variants of simple integer loops, without branching in the loop body and with affine constraints as the loop guard (and possibly a precondition). We show that termination of such loops is undecidable in some cases, in particular, when the body of the loop is expressed by a set of linear inequalities where the coefficients are from Z ∪ {
r
} with
r
an arbitrary irrational; when the loop is a sequence of instructions, that compute either linear expressions or the step function; and when the loop body is a piecewise linear deterministic update with two pieces. The undecidability result is proven by a reduction from counter programs, whose termination is known to be undecidable. For the common case of integer linear-constraint loops with rational coefficients we have not succeeded in proving either decidability or undecidability of termination, but we show that a Petri net can be simulated with such a loop; this implies some interesting lower bounds. For example, termination for a partially specified input is at least EXPSPACE-hard.
Bisimulation for Quantum Processes
Authors: Feng Yuan , Duan Runyao , Ying Mingsheng
Published: January 2013

Quantum cryptographic systems have been commercially available, with a striking advantage over classical systems that their security and ability to detect the presence of eavesdropping are provable based on the principles of quantum mechanics. On the other hand, quantum protocol designers may commit more faults than classical protocol designers since human intuition is poorly adapted to the quantum world. To offer formal techniques for modeling and verification of quantum protocols, several quantum extensions of process algebra have been proposed. An important issue in quantum process algebra is to discover a quantum generalization of bisimulation preserved by various process constructs, in particular, parallel composition, where one of the major differences between classical and quantum systems, namely quantum entanglement, is present. Quite a few versions of bisimulation have been defined for quantum processes in the literature, but in the best case they are only proved to be preserved by parallel composition of purely quantum processes where no classical communication is involved.

Many quantum cryptographic protocols, however, employ the LOCC (Local Operations and Classical Communication) scheme, where classical communication must be explicitly specified. So, a notion of bisimulation preserved by parallel composition in the circumstance of both classical and quantum communication is crucial for process algebra approach to verification of quantum cryptographic protocols. In this article we introduce novel notions of strong bisimulation and weak bisimulation for quantum processes, and prove that they are congruent with respect to various process algebra combinators including parallel composition even when both classical and quantum communication are present. We also establish some basic algebraic laws for these bisimulations. In particular, we show the uniqueness of the solutions to recursive equations of quantum processes, which proves useful in verifying complex quantum protocols. To capture the idea that a quantum process approximately implements its specification, and provide techniques and tools for approximate reasoning, a quantified version of strong bisimulation, which defines for each pair of quantum processes a bisimulation-based distance characterizing the extent to which they are strongly bisimilar, is also introduced.
The myrmics memory allocator
Authors: Lyberis Spyros , Pratikakis Polyvios , Nikolopoulos Dimitrios S. , Schulz Martin , Gamblin Todd , de Supinski Bronis R.
Published: January 2013

Constantly increasing hardware parallelism poses more and more challenges to programmers and language designers. One approach to harness the massive parallelism is to move to task-based programming models that rely on runtime systems for dependency analysis and scheduling. Such models generally benefit from the existence of a global address space. This paper presents the parallel memory allocator of the Myrmics runtime system, in which multiple allocator instances organized in a tree hierarchy cooperate to implement a global address space with dynamic region support on distributed memory machines. The Myrmics hierarchical memory allocator is step towards improved productivity and performance in parallel programming. Productivity is improved through the use of dynamic regions in a global address space, which provide a convenient shared memory abstraction for dynamic and irregular data structures. Performance is improved through scaling on manycore systems without system-wide cache coherency. We evaluate the stand-alone allocator on an MPI-based x86 cluster and find that it scales well for up to 512 worker cores, while it can outperform Unified Parallel C by a factor of 3.7-10.7x.
Eliminating read barriers through procrastination and cleanliness
Authors: Sivaramakrishnan KC , Ziarek Lukasz , Jagannathan Suresh
Published: January 2013

Managed languages typically use read barriers to interpret forwarding pointers introduced to keep track of copied objects. For example, in a multicore environment with thread-local heaps and a global, shared heap, an object initially allocated on a local heap may be copied to a shared heap if it becomes the source of a store operation whose target location resides on the shared heap. As part of the copy operation, a forwarding pointer may be established in the original object to point to the copied object. This level of indirection avoids the need to update all of the references to the object that has been copied.

In this paper, we consider the design of a managed runtime that eliminates read barriers. Our design is premised on the availability of a sufficient degree of concurrency to stall operations that would otherwise necessitate the copy. Stalled actions are deferred until the next local collection, avoiding exposing forwarding pointers to the mutator. In certain important cases, procrastination is unnecessary -- lightweight runtime techniques can sometimes be used to allow objects to be eagerly copied when their set of incoming references is known, or when it can be determined that having multiple copies would not violate program semantics.

We evaluate our techniques on 3 platforms: a 16-core AMD64 machine, a 48-core Intel SCC, and an 864-core Azul Vega 3. Experimental results over a range of parallel benchmarks indicate that our approach leads to notable performance gains (20 - 32% on average) without incurring any additional complexity.
Scalable concurrent and parallel mark
Authors: Iyengar Balaji , Gehringer Edward , Wolf Michael , Manivannan Karthikeyan
Published: January 2013

Parallel marking algorithms use multiple threads to walk through the object heap graph and mark each reachable object as live. Parallel marker threads mark an object "live" by atomically setting a bit in a mark-bitmap or a bit in the object header. Most of these parallel algorithms strive to improve the marking throughput by using work-stealing algorithms for load-balancing and to ensure that all participating threads are kept busy. A purely "processor-centric" load-balancing approach in conjunction with a need to atomically set the mark bit, results in significant contention during parallel marking. This limits the scalability and throughput of parallel marking algorithms.

We describe a new non-blocking and lock-free, work-sharing algorithm, the primary goal being to reduce contention during atomic updates of the mark-bitmap by parallel task-threads. Our work-sharing mechanism uses the address of a word in the mark-bitmap as the key to stripe work among parallel task-threads, with only a subset of the task-threads working on each stripe. This filters out most of the contention during parallel marking with 20% improvements in performance.

In case of concurrent and on-the-fly collector algorithms, mutator threads also generate marking-work for the marking task-threads. In these schemes, mutator threads are also provided with thread-local marking stacks where they collect references to potentially "gray" objects, i.e., objects that haven't been "marked-through" by the collector. We note that since this work is generated by mutators when they reference these objects, there is a high likelihood that these objects continue to be present in the processor cache. We describe and evaluate a scheme to distribute mutator generated marking work among the collector's task-threads that is cognizant of the processor and cache topology. We prototype both our algorithms within the C4 [28] collector that ships as part of an industrial strength JVM for the Linux-X86 platform.