Miracle-dz/UniFAR-FTUs huggingface dataset:
Implied Correlation Index: A New Measure of Diversification

Most approaches in forecasting future correlation depend on the use of historical information as their basic information set. Recently, there have been some attempts to use the notion of “implied” correlation as a more accurate measure of future correlation. This study proposes an innovative methodology for backing‐out implied correlation measures from index options. This new measure called implied correlation index reflects the market view of the future level of the diversification in the market portfolio represented by the index. The methodology is applied to the Dow Jones Industrial Average index, and the statistical properties and the dynamics of the proposed implied correlation measure are examined. The evidence of this study indicates that the implied correlation index fluctuates substantially over time and displays strong dynamic dependence. Moreover, there is a systematic tendency for the implied correlation index to increase when the market index returns decrease and/or the market volatility increases, indicating limited diversification when it is needed most. Finally, the forecast performance of the implied correlation index is assessed. Although the implied correlation index is a biased forecast of realized correlation, it has a high explanatory power, and it is orthogonal to the information set compared to a historical forecast. © 2005 Wiley Periodicals, Inc. Jrl Fut Mark 25:171–197, 2005
A Management Tool for the Replication of Operating Systems in Wireless Communication Networks

To simplify computer management, various administration systems based on wired connections adopt advanced techniques to manage software configuration. Nevertheless, the strong relation between hardware and software makes for an individualism of that management, besides penalizing computational mobility and ubiquity. All these issues lead to degradation of scalability, flexibility and the facility to install and maintain distributed applications. This article presents an environment for centralized wireless communication network management, named WSE-OS (Wireless Sharing Environment -- Operating Systems): a model based on Virtual Desktop Infrastructure (VDI) which associates virtualization techniques and safe remote access systems to create a distributed architecture as a base for a managing system. WSE-OS is capable of accomplishing the replication of operating system images using wireless communication network, besides offering abstraction of hardware to its clients, making the management more flexible and independent of wired connections. Results obtained from this work indicate that WSE-OS allows disseminating, through a single software configuration, the execution of data related to operating system images in client computers. WSE-OS can also be used as a management tool for operating systems in a wireless network.
MODELING AND VISUALIZATION OF CLOUDS FROM REAL WORLD DATA

Visualization of gaseous phenomena, such as smoke, fire or clouds has been a challenging issue in computer graphics due to the complicated geometry of such natural objects. In the early 80's, approaches that faced this problem tried to simplify the representation of such geometry, using simple particles or ellipsoids. During the last decade work was done on rendering fractal volumes and random textures in order to create a realistic turbulent image of random generated volumes, and in parallel, modeling of soft or 'blobby' objects (also known as 'metaballs') was combined with hardware accelerated volume rendering and gave some first convincing images of 3D gas volumes in near realtime. There has been large technological developments in the computer graphics hardware and a lot of work has been done from the computer graphics community on simulation of clouds, still there is not much done in the direction of modeling and rendering of such objects from real world measurements, and work is lacking on the issues that arise from datasets with incomplete spatial ot temporal resolution. In the presented work we use the modeling technique of metaballs based on cloud bottom and top height measurements taken during the CLOUDMAP2 project, in order to construct a 3D volume from point clouds. We present the problems that arise from fitting the volume to the measured points, combination of cloud top and bottom height estimations with different resolutions and the generation of large volume data. Solutions to these problems are presented which include the calculation of cloud volumes, interpolation with cloud top height estimations from simultaneous ground based and satellite observations and finally we present various methods to render such volumes using hardware and software assisted techniques.
Contradicted and initially stronger effects in highly cited clinical research.

CONTEXT Controversy and uncertainty ensue when the results of clinical research on the effectiveness of interventions are subsequently contradicted. Controversies are most prominent when high-impact research is involved. OBJECTIVES To understand how frequently highly cited studies are contradicted or find effects that are stronger than in other similar studies and to discern whether specific characteristics are associated with such refutation over time. DESIGN All original clinical research studies published in 3 major general clinical journals or high-impact-factor specialty journals in 1990-2003 and cited more than 1000 times in the literature were examined. MAIN OUTCOME MEASURE The results of highly cited articles were compared against subsequent studies of comparable or larger sample size and similar or better controlled designs. The same analysis was also performed comparatively for matched studies that were not so highly cited. RESULTS Of 49 highly cited original clinical research studies, 45 claimed that the intervention was effective. Of these, 7 (16%) were contradicted by subsequent studies, 7 others (16%) had found effects that were stronger than those of subsequent studies, 20 (44%) were replicated, and 11 (24%) remained largely unchallenged. Five of 6 highly-cited nonrandomized studies had been contradicted or had found stronger effects vs 9 of 39 randomized controlled trials (P = .008). Among randomized trials, studies with contradicted or stronger effects were smaller (P = .009) than replicated or unchallenged studies although there was no statistically significant difference in their early or overall citation impact. Matched control studies did not have a significantly different share of refuted results than highly cited studies, but they included more studies with "negative" results. CONCLUSIONS Contradiction and initially stronger effects are not unusual in highly cited research of clinical interventions and their outcomes. The extent to which high citations may provoke contradictions and vice versa needs more study. Controversies are most common with highly cited nonrandomized studies, but even the most highly cited randomized trials may be challenged and refuted over time, especially small ones.
Bound dipole solitary solutions in anisotropic nonlocal self-focusing media

The possibility of creating two-transverse-dimensional @~2 11! D# soliton-type structures of light in nonlinear media is of considerable interest due to potential applications in opti- cal information processing systems @1#. The dynamics of nonlinear propagation equations resulting in the formation of such structures can be very complex and may result in the generation of higher-order and multisoliton solutions. These solutions have been investigated extensively in the one- transverse-dimensional @~111! D# case @2#. A number of ex- act analytical methods have been developed, including the inverse scattering method, which provides an exact solution of an initial-value problem, Backlund transformations, and Lax pairs. Examples of higher-order bound soliton solutions include the formation of soliton-antisoliton pairs ~kinks ! @ 3 # , incoherently coupled bright and dark beams @4#, and multi- soliton solutions of a set of coupled high-order nonlinear Schrodinger equations @5#. In two-transverse dimensions the majority of nonlinear equations of interest are not integrable, and the correspond- ing initial or boundary-value problems are usually analyzed numerically. The analysis of a single-soliton solution if it does not exhibit a simplifying ~e.g., radial! symmetry may require sophisticated tools @6#. The existence and properties of higher-order and multisoliton solutions in the ~211! D case have therefore been investigated much less than in the ~111! D case. Noteworthy results include calculation of non- linear dipolar structures in the context of the Korteweg-de Vries equation @7#, molecular matrices with impurities @8#, and fluids @9#. Higher-order radially symmetric structures in media with cubic nonlinearity were given in @10#, and their evolution in a saturating nonlinear medium studied in @11#. More complex localized solutions are described in @12#. In this paper we find and investigate ~211! D dipole soli- tary solutions for a light beam in a self-focusing nonlocal anisotropic optical medium. This solution is a bound pair consisting of two elliptical beams spaced some distance apart that are in antiphase to each other ~have a p relative phase shift! The above dipole solution is unique to the ~211! D case and has no analogs in the ~111! D case for neither an- isotropic nor Kerr-type isotropic nonlinear media. Evidence of a related bound-pair solution for a defocusing nonlinearity was reported recently in @13#. We demonstrate experimen- tally the importance of the relative phase of the two lobes of the dipole in determining the subsequent spatial evolution. The particulars of our analysis pertain to a photorefractive nonlinear response, but general conclusions should be quali- tatively applicable to other media. Our analysis is based on the set of equations @14#
Firwire Camera Calibration for Video See-through Augmented Reality System

Augmented reality is a kind of technology in which the user’s view of the real world is overlaid (combined) by virtual graphic model. For video see-through augmented reality system, camera calibration is one of important issues since real environment images come from video camera. We designed a calibration tool which helped us to calculate the extrinsic camera parameters (camera pose). We focused on the easiness and accuracy of the calibration procedure and presented a new method that is both simple to implement and efficient. Also, it is different from the typical calibration procedure because we used 6 DoF tracking system to get the coordinate data of fiducials. The original target and virtual counterpart are shown on the same video image to verify the correctness of extrinsic parameters. The results are precise enough to be applied on initial experimental application of augmented reality. Key-Words: Camera calibration,Augmented reality,Firewire, Tsai’s model
High quality streaming system with hierarchical cache servers based on inter-stream FEC function

Video streaming using hierarchical cache servers is effective to provide high quality services to many users. However, less-accessed videos tend to be sparsely cached on cache servers far from users. Streaming qualities are degraded due to relatively high packet loss rate and long delay. In order to address the issues on heavy and bursty packet loss over such long distance transmission, we have focused on recovery characteristic of a multi-server Forward Error Correction (FEC) function named “Inter-Stream FEC. ” In this paper, we propose a high quality streaming system exploiting hierarchical cache servers. The proposed system improves users' experience by adaptively applying Inter-Stream FEC. We also propose a parity data request method combines with parity server selection considering cache status of individual server and disjointness between paths. Simulation results show the proposed system can achieve higher restoration performance compared with a streaming system using traditional FEC, particularly when bursty loss occurs.
Star formation around the H ii region Sh2-235

We present a picture of star formation around the HII region Sh2-235 (S235) based upon data on the spatial distribution of young stellar clusters and the distribution and kinematics of molecular gas around S235. We observed 13CO(1-0) and CS(2-1) emission toward S235 with the Onsala Space Observatory 20-m telescope and analysed the star density distribution with archival data from the Two Micron All-Sky Survey (2MASS). Dense molecular gas forms a shell-like structure at the southeastern part of S235. The young clusters found with 2MASS data are embedded in this shell. The positional relationship of the clusters, the molecular shell and the HII region indicates that expansion of S235 is responsible for the formation of the clusters. The gas distribution in the S235 molecular complex is clumpy, which hampers interpretation exclusively on the basis of the morphology of the star-forming region. We use data on kinematics of molecular gas to support the hypothesis of induced star formation, and distinguish three basic types of molecular gas components. The first type is primordial undisturbed gas of the giant molecular cloud, the second type is gas entrained in motion by expansion of the HII region (this is where the embedded clusters were formed) and the third type is a fast-moving gas, which might have been accelerated by winds from the newly formed clusters. The clumpy distribution of molecular gas and its kinematics around the HII region implies that the picture of triggered star formation around S235 can be a mixture of at least two possibilities: the `collect-and-collapse' scenario and the compression of pre-existing dense clumps by the shock wave.
XCP for shared-access multi-rate media

The eXplicit Control Protocol (XCP) was developed to overcome some of the limitations of TCP, such as low utilization in high bandwidth delay product networks, unstable throughput, large queue build-up, and limited fairness. XCP, however, requires that each queue controller in a path knows the exact capacity of its link. In shared access media, e.g. IEEE 802.11, knowing the actual capacity of the channel is a difficult task.In this paper we propose modifications to the XCP algorithm that enable the utilization of XCP even when the capacity of a link is unknown. These modifications are validated through simulation.We also present the results of a comparison between the performance of the modified XCP and TCP, where XCP controlled flows result more stable, fairness increases, and the network delay becomes lower. In addition, as the bandwidth delay product increases, XCP is able to maintain near-maximum utilization while TCP decreases utilization.
The Incremental Prognostic Value of Cardiac Computed Tomography in Comparison with Single-Photon Emission Computed Tomography in Patients with Suspected Coronary Artery Disease

Background Coronary computed tomographic angiography (CCTA) facilitates comprehensive evaluation of coronary artery disease (CAD), including plaque characterization, and can provide additive diagnostic value to single-photon emission computed tomography (SPECT). However, data regarding the incremental prognostic value of CCTA to SPECT remain sparse. We evaluated the independent and incremental prognostic value of CCTA, as compared with clinical risk factors and SPECT. Materials and methods A total of 1,077 patients with suspected CAD who underwent both SPECT and cardiac CT between 2004 and 2012 were enrolled retrospectively. Presence of reversible or fixed perfusion defect (PD) and summed stress score were evaluated on SPECT. Presence, extent of coronary atherosclerosis and diameter stenosis (DS) were evaluated on CCTA. Plaque composition was categorized as non-calcified, mixed, or calcified according to the volume of calcified component (>130 Hounsfield Units). Patients were followed up for the occurrence of adverse cardiac events including cardiac death, non-fatal myocardial infarction, unstable angina, and late revascularization (>90 days after imaging studies). Results During follow-up (median 23 months), adverse cardiac events were observed in 71 patients (6.6%). When adjusted for clinical risk factors and SPECT findings, the presence of any coronary plaque, any plaque in ≥3 segments, coronary artery calcium score (CACS) ≥400, a plaque ≥50% DS, presence of non-calcified plaque (NCP) or mixed plaque (MP), and NCP/MP in ≥2 segments were independent predictors of adverse cardiac events; however, the presence of calcified plaque (CP) was not. Conventional CCTA findings, including CACS ≥400 and a plaque ≥50% DS, demonstrated incremental prognostic value over clinical risk factors and SPECT (χ² 54.19 to 101.03; p <0.001). Addition of NCP/MP in ≥2 segments resulted in further significantly improved prediction (χ² 101.03 to 113.29; p <0.001). Conclusion Comprehensive CCTA evaluation of coronary atherosclerosis provides independent and incremental prognostic value in relation to SPECT evaluation of myocardial ischemia. Specifically, segmentally-analyzed plaque composition with CCTA provides further risk stratification in addition to CACS and DS.
PDE-Based Enhancement Algorithm for Dim-Target Images

In order to improve discrimination of the detailed information of dim-target images, the authors propose a new PDE-based nonlinear image enhancement algorithm, which takes the spreading speed of images that vary with the size and direction of the gradient. As a result, the dim-target images can be adaptively enhanced locally, the edges are retained better, and the false edges and the "ladder-effect" are eliminated. Furthermore, the visual effect is improved and processing is more efficient. The experimental simulation results show that the algorithm has higher LSCR and higher GSCR than the traditional methods, and image processing efficiency is greatly increased.
A Survey on Service Composition Approaches : From Industrial Standards to Formal Methods ?

Composition of services has received much interest to support business-to-business and enterprise applications integration. The business world has developed a number of XML-based standards to formalize the specification of web services, their composition and their execution. On the other hand, the semantic web community focuses on reasoning about web resources by explicitly declaring their preconditions and effects with terms defined precisely in ontologies. Current service composition approaches range from practical languages aspiring to become industrial standards (e.g. BPEL and OWL-S) to more theoretical models and languages (e.g. automata, Petri nets, and process algebras). In this paper we present a survey of existing proposals for service composition and compare them among each other with respect to some key requirements. We hope this helps service composition designers and developers to focus their efforts and to deliver lasting solutions, while at the same time addressing the technology’s critical needs.
Evaluation of a Transparent Wall System for Residential Construction

A new type of transparent panelized wall system for residential construction has recently been developed that can be used as an alternative to typical wood-frame and other light-frame wall systems. The new wall system is a prefabricated wall panel consisting of a structural steel back-up frame, transparent polycarbonate sheathing, and a curtain- wall system that may contain an integrated photovoltaic glazing panel. In this paper, after an introduction to the structural and architectural aspects of system, the thermal and energy performance aspects of this wall system are evaluated based on several criteria. The current configuration of the wall system shows an overall U-factor of 1.585 W/m 2 k. The material and systems analysis using a combination of life-cycle assessment and embodied energy are discussed as well. The embodied energy of the system turns out to be approximately two and a half times that of conventional wood-frame system. The paper provides some concluding remarks regarding the sustainability aspects.
Variations in chemical fingerprints and major flavonoid contents from the leaves of thirty‐one accessions of Hibiscus sabdariffa L.

Abstract The leaves of Hibiscus sabdariffa L. have been used as traditional folk medicines for treating high blood pressure and fever. There are many accessions of H. sabdariffa L. throughout the world. To assess the chemical variations of 31 different accessions of H. sabdariffa L. , fingerprinting analysis and quantitation of major flavonoids were performed by high‐performance liquid chromatography (HPLC). The HPLC method was validated for linearity, sensitivity, precision, repeatability and accuracy. A quadrupole‐time‐of‐flight mass spectrometry (Q‐TOF‐MS) was applied for the characterization of major compounds. A total of 9 compounds were identified, including 6 flavonoids and 3 phenolic acids. In the fingerprint analysis, similarity analysis (SA) and principal component analysis (PCA) were used to differentiate the 31 accessions of H. sabdariffa L. Based on the results of PCA and SA, the samples No. 15 and 19 appeared much different from the main group. The total content of five flavonoids varied greatly among different accessions, ranging from 3.35 to 23.30 mg/g. Rutin was found to be the dominant compound and the content of rutin could contribute to chemical variations among different accessions. This study was helpful to understand the chemical variations between different accessions of H. sabdariffa L. , which could be used for quality control. © 2015 The Authors Biomedical Chromatography Published by John Wiley & Sons Ltd.
Repetitive Transcranial Magnetic Stimulation Promotes Neural Stem Cell Proliferation via the Regulation of MiR-25 in a Rat Model of Focal Cerebral Ischemia

Repetitive transcranial magnetic stimulation (rTMS) has increasingly been studied over the past decade to determine whether it has a therapeutic benefit on focal cerebral ischemia. However, the underlying mechanism of rTMS in this process remains unclear. In the current study, we investigated the effects of rTMS on the proliferation of adult neural stem cells (NSCs) and explored microRNAs (miRNAs) that were affected by rTMS. Our data showed that 10 Hz rTMS significantly increased the proliferation of adult NSCs after focal cerebral ischemia in the subventricular zone (SVZ), and the expression of miR-25 was obviously up-regulated in the ischemic cortex after rTMS. p57, an identified miR-25 target gene that regulates factors linked to NSC proliferation, was also evaluated, and it exhibited down-regulation. To further verify the role of miR-25, rats were injected with a single dose of antagomir-25 and were subjected to focal cerebral ischemia followed by rTMS treatment. The results confirmed that miR-25 could be repressed specifically and could drive the up-regulation of its target gene (p57), which resulted in the inhibition of adult NSC proliferation in the SVZ after rTMS. Thus, our studies strongly indicated that 10 Hz rTMS can promote the proliferation of adult NSCs in the SVZ after focal cerebral ischemia by regulating the miR-25/p57 pathway.