bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theoretical analysis of the influence of band tail defects on PIN InGaN solar cells
Authors: Wang Baozhu , Feng Yan , Meng Lizhi , Wang Min , Xiao Hongling , Wang Xiaoliang 
Published: January 2016

AbstractInGaN solar cells have higher conversion efficiency than traditional Si based solar cells. However, efficiency of experimental InGaN solar cell is lower than expected. There are still several problems, such as the structure design of InGaN solar cells, the quality of InGaN materials, need to be discussed and solved. Thus, the researches of structure design and defect effects are important for the implications of InGaN solar cells. The performance of p‐GaN/i‐InxGa1–x/n‐GaN solar cells with different In content is simulated by AMPS‐1D. It is found that the optimum efficiency of p‐GaN/i‐InxGa1–xN/n‐GaN solar cells is 8.9% when the In content is 0.26. The p‐GaN/i‐In0.26Ga0.74/n‐GaN solar cells with band tail defects are simulated. The simulated results show the efficiency decreases with the increase of the E‐character. And the efficiency decreases sharply from 8.30% to 7.19% when the capture cross section is 10–14 cm–2. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparison of silicon, SiC and GaN power transistor technologies with breakdown voltage rating from 1.2 kV to 15 kV
Authors: Chowdhury Sauvik , Guo Zhibo , Liu Xueqing , Chow T. Paul 
Published: January 2016

AbstractIn recent years, different power transistors have been developed in silicon carbide (SiC) and gallium nitride (GaN) as replacements for silicon based IGBTs. This paper presents a simulation comparison of the static and dynamic performance of silicon IGBTs with different SiC and GaN based lateral and vertical power transistors (HEMT, MOSFET and IGBT) with breakdown voltage ratings between 1.2 kV to 15 kV. The strengths and weaknesses of different technologies which make them suitable at different voltage levels have been discussed. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Semi‐polar (11‐22) GaN grown on patterned (113) Si substrate
Authors: Yu Xiang , Hou Yaonan , Shen Shuoheng , Bai Jie , Gong Yipin , Zhang Yun , Wang Tao 
Published: January 2016

AbstractAn epitaxial growth technic has been developed to synthesize semi‐polar (11‐22) GaN on (113) Si substrate with inverted‐pyramid patterns. The reaction between Ga and Si substrate has been successfully solved by simply depositing a thin SiO2 layer on selective regions of the substrate before growth. High quality semi‐polar (11‐22) GaN‐on‐Si with a smooth surface has been obtained after delicately tuning growth conditions. Based on the scanning electron microscopy and x‐ray diffraction characterizations, a model has been well established to illuminate the growth process. Due to the very low density of defects confirmed by transmission electron microscopy, our sample demonstrates an excellent optical property, which is promising for efficient optoelectronic devices using GaN‐on‐Si configuration. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
AD‐ASGKA – authenticated dynamic protocols for asymmetric group key agreement
Authors: Li Mingchu , Xu Xiaodong , Guo Cheng , Tan Xing 
Published: January 2016

AbstractAsymmetric group key agreement is a cryptographic primitive allowing a group of users to negotiate a common public encryption key while each of them holds a different secret private decryption key. Anyone (including outsiders) with the public encryption key can send encrypted messages to the group members, and then the group members can decrypt the messages. Authenticated key agreement protocols authenticate the identities of users to ensure that only the intended group members can establish a session in which the group members can communicate with each other. Dynamic asymmetric group key agreement concerns about the scenarios such as ad hoc networks in which the group members may join or leave at any given time. In this paper, we propose a one‐round authenticated dynamic protocol for symmetric group key agreement. For efficiency reasons, we employ the identity‐based public‐key cryptography (IB‐PKC) to authenticate users rather than the public key infrastructure and the certificate‐less public‐key cryptography. Our analysis shows that the proposals in the paper can resist active attacks and meet many desirable security attributes. Besides, our protocol allows users to join or leave the group at the same time. Furthermore, our protocol is round‐optimal and has a quite good performance as compared with previous works. Copyright © 2016 John Wiley & Sons, Ltd.
Correct-by-construction model driven engineering composition operators
Authors: Kezadri Hamiaz Mounira , Pantel Marc , Thirioux Xavier , Combemale Benoit 
Published: January 2016

Abstract
Model composition is a crucial activity in Model Driven Engineering both to reuse validated and verified model elements and to handle separately the various aspects in a complex system and then weave them while preserving their properties. Many research activities target this compositional validation and verification (V & V) strategy: allow the independent assessment of components and minimize the residual V & V activities at assembly time. However, there is a continuous and increasing need for the definition of new composition operators that allow the reconciliation of existing models to build new systems according to various requirements. These ones are usually built from scratch and must be systematically verified to assess that they preserve the properties of the assembled elements. This verification is usually tedious but is mandatory to avoid verifying the composite system for each use of the operators. Our work addresses these issues, we first target the use of proof assistants for specifying and verifying compositional verification frameworks relying on formal verification techniques instead of testing and proofreading. Then, using a divide and conquer approach, we focus on the development of elementary composition operators that are easy to verify and can be used to further define complex composition operators. In our approach, proofs for the complex operators are then obtained by assembling the proofs of the basic operators. To illustrate our proposal, we use the Coq proof assistant to formalize the language-independent elementary composition operators Union and Substitution and the proof that the conformance of models with respect to metamodels is preserved during composition. We show that more sophisticated composition operators that share parts of the implementation and have several properties in common (especially: aspect oriented modeling composition approach, invasive software composition, and package merge) can then be built from the basic ones, and that the proof of conformance preservation can also be built from the proofs of basic operators.
Anatomical Resection But Not Surgical Margin Width Influence Survival Following Resection for HCC, A Propensity Score Analysis
Authors: Lee Jung‐Woo , Lee Young‐Joo , Park Kwang‐Min , Hwang Dae‐Wook , Lee Jae Hoon , Song Ki Byung 
Published: January 2016

AbstractBackgroundThe effects of the surgical resection margin on the clinical outcomes in hepatocellular carcinoma (HCC) cases remain controversial. The objective of this study was to further examine this issue.MethodsThe details of all HCC patients who underwent hepatectomy between December 1999 and December 2009 at the Division of Hepatobiliary and Pancreas Surgery, Asan Medical Center were analyzed retrospectively. We divided 1022 HCC patients into two groups according to the most significant surgical margin length. To overcome any bias due to differences in the distribution of covariates between the two groups, the patients were in a matched 1:1 ratio by propensity score analysis.
ResultsA surgical margin ≤1 mm was identified as the most significant surgical margin in both disease‐free survival (DFS) and overall survival (OS) (p = 0.008 and p = 0.026, respectively). However, many clinicopathological factors were different between the resection margin ≤1 mm and >1 mm groups. To reduce these different clinicopathological factors, propensity score matching was performed using 21 selected factors. After matching, no significant difference was found in DFS and OS between the two groups (p = 0.688, p = 0.398). In addition, there was no significant difference in the intrahepatic recurrence rate and pattern between the resection margin groups. Except for the preoperative patient’s status and tumor stage, significant risk factors in OS were anatomical resection and postoperative morbidity (p = 0.002, p = 0.001).ConclusionWe identified that the widths of the resection margin in resectable hepatocellular carcinoma did not influence the postoperative recurrence rates, overall survival, and recurrence pattern in multivariable analysis as well as propensity score match analysis.
Canadian Experience with Fingolimod: Adherence to Treatment and Monitoring
Authors: Lapierre Yves , O’Connor Paul , Devonshire Virginia , Freedman Mark S , Kremenchutzky Marcelo , Yeung Michael , Schecter Robyn 
Published: January 2016

AbstractBackground: The Canadian GILENYA® Go ProgramTM provides education and support to people with relapsing-remitting multiple sclerosis during fingolimod treatment. Methods: Data were collected and analyzed from the time of the first individual enrolled in March 2011 to March 31, 2014. Individuals were excluded if they withdrew from the program prior to receiving the first dose, or had not completed the first dose observation (FDO) at the time of data cut-off. Reports of adverse effects were validated with a database of adverse events reported to Novartis Pharmaceuticals Canada Inc. Results: A total of 2,399 individuals had completed FDO at the end of the three-year observation period. Mean age was 41.2 years; 75.2% were female. The most recent prior therapies reported were interferon-β agents (50.2%), glatiramer acetate (31.1%), natalizumab (14.2%), no prior therapy (3.3%), and other agent (1.1%). Reasons for switching to fingolimod were lack of efficacy (34.9%), side effects (34.6%), and dissatisfaction with injections/infusion (30.4%). Continuation rates with fingolimod at 12, 24 and 30 months were 80.7%, 76.6% and 76.0%, respectively. The discontinuation rate due to reported lack of efficacy during the three-year period was 1.3%. There was 94.4% adherence to the scheduled ophthalmic examination. Conclusions: The GILENYA® Go ProgramTM captures data for virtually all fingolimod-treated patients in Canada, enabling the evaluation of fingolimod use in routine practice. Ongoing patient support and reminders to take the medication, in conjunction with physicians’ and/or patients’ perception of the efficacy and tolerability of fingolimod, resulted in a high rate of continuation during longer-term therapy.
Springs and their offspring: the international consequences of domestic uprisings
Authors: Owen John M. 
Published: January 2016

AbstractA politicalspringis an abrupt, broad, sustained increase in public dissent in a state that has prohibited it, as in Czechoslovakia in 1968 or Tunisia in early 2011. Some springs produce offspring – clusters of events within neighbouring states (civic unrest, increased state repression, co-option of dissent, revolution) and among those states (intensification of international rivalries, foreign interventions). An English Spring in 1558–9 produced such a cluster in Northwestern Europe. This article addresses the underlying causal mechanism connecting springs and their offspring, rather than the related correlational question (viz. under what conditions a spring is followed by offspring). That mechanism istransnational group polarisation, or the progressive separation of preferences across a population into pro- and anti-government groups. Transnational polarisation along a pro-versus-anti-government axis is an endogenous process triggered by exogenous events, such as violence or public demonstrations that raise the status of, or threat to, one of the groups. It presents powerful actors across states with new threats and opportunities and can help explain how the Tunisian Spring of early 2011 produced throughout the Arab Middle East infectious unrest, serial repressions and reforms, heightened international tensions, and foreign interventions.
Future arms, technologies, and international law: Preventive security governance
Authors: Garcia Denise 
Published: January 2016

AbstractThis article presents an initial discussion of the political and legal challenges associated with weaponised technologies in three interconnected areas that may impinge upon the ability to protect civilian populations during peace and war and imperil international security: armed unmanned combat aerial vehicles (commonly known as drones); autonomous weapons systems (known as ‘killer robots’); and the potential militarisation of cyberspace, or its use as a weapon, and the operation of drones and killer robots in the cyber domain. Supporting the argument that the world is ‘facing new methods of warfare’ and that international security governance and law are not keeping up, the article provides an overview and interpretation of three technologies in connection with aspects of five branches of law: state responsibility, use of force, international humanitarian law, human rights law, and law of the commons. I argue therefore that ‘preventive security governance’ could be a strategy to curtail uncertainty in the preservation of stability and international order. I define ‘preventive security governance’ as the codification of specific or new global norms, arising from existing international law that will clarify expectations and universally agreed behaviour on a given issue-area. This is essential for a peaceful future for humanity and for international order and stability.
Radio Emission from Binary Stars in the AB Doradus Moving Group
Authors: Azulay R. , Guirado J.C. , Marcaide J.M. , Martí-Vidal I. , Ros E. 
Published: January 2016

AbstractPrecise determination of dynamical masses of pre-main-sequence stars is essential for calibrating stellar evolution models, that are widely used to derive theoretical masses of young low-mass objects. We have determined the individual masses of the pair AB Dor Ba/Bb using Australian Long Baseline Array observations and archive infrared data, as part of a larger program directed to monitor binary systems in the AB Doradus moving group. We have detected, for the first time, compact radio emission from both stars. This has allowed us to determine the orbital parameters of both the relative and absolute orbits and, consequently, their individual dynamical masses: 0.28±0.05 M⊙ and 0.25±0.05 M⊙. Comparisons of the dynamical masses with the prediction of pre-main-sequence (PMS) evolutionary models show that the models underpredict the dynamical masses of the binary components Ba and Bb by 10–30% and 10–40%, respectively.
Collisions of Planetesimals and Formation of Planets
Authors: Dvorak Rudolf , Maindl Thomas I. , Süli Áron , Schäfer Christoph M. , Speith Roland , Burger Christoph 
Published: January 2016

AbstractWe present preliminary results of models of terrestrial planet formation using on the one hand classical numerical integration of hundreds of small bodies on CPUs and on the other hand—for comparison—the results of our GPU code with thousands of small bodies which then merge to larger ones. To be able to determine the outcome of collision events we use our smooth particle hydrodynamics (SPH) code which tracks how water is lost during such events.
On the Possibility to Identify a Companion in a Protoplanetary Disk
Authors: Zakhozhay O. V. 
Published: January 2016

AbstractIn this paper, I investigate a possibility to detect a brown dwarf companion in a protoplanetary disk based on spectral energy distribution (SED) profile analysis. I present synthetic spectral energy distributions of protoplanetary disks with and without an embedded companion that clears a gap. The computations are performed for a star (0.8 M⊙) and a substellar companion (30 MJ) at an age of 5 Myr embedded in a protoplanetary disk, located at a distance 100 pc from the Sun. Analysis of the SED profile shape indicates that the maximum difference between the fluxes of the systems with and without the companion is ≈ 0.43 Jy at 34 μm.
X-raying Circumstellar Material around Young Stars
Authors: Schneider P. C. , Günther H. M. 
Published: January 2016

AbstractYoung stars are surrounded by copious amounts of circumstellar material. Its composition, in particular its gas-to-dust ratio, is an important parameter. However, measuring this ratio is challenging, because gas mass estimates are often model dependent. X-ray absorption is sensitive to the gas along the line-of-sight while optical/near-IR extinction depends on the dust. Therefore, the absorber's gas-to-dust ratio is directly given by the ratio between X-ray and optical/near-IR extinction. We present three systems where we used X-ray and optical/near-IR data to constrain the gas-to-dust ratio of circumstellar material; from a dust rich debris disk to gaseous protoplanetary disks.
New Low-mass Accretors in the Scorpius-Centaurus OB Association
Authors: Murphy Simon J. , Lawson Warrick A. , Bento Joao 
Published: January 2016

AbstractWe describe the serendipitous discovery of two new lithium-rich M5 members of the Scorpius-Centaurus OB Association (Sco-Cen). Both stars exhibit large 12 and 22 μm excesses and strong, variable Hα emission which we attribute to accretion from circumstellar discs. Such stars are thought to be incredibly rare at the ~16 Myr median age of much of Sco-Cen. The serendipitous discovery of two accreting stars hosting large quantities of circumstellar material may be indicative of a sizeable age spread in Sco-Cen, or further evidence that disc dispersal and planet formation time-scales are longer around lower-mass stars.
Stellar Evolution Models of Young Stars: Progress and Limitations
Authors: Feiden Gregory A. 
Published: January 2016

AbstractStellar evolution models are a cornerstone of young star astrophysics, which necessitates that they yield accurate and reliable predictions of stellar properties. Here, I review the current performance of stellar evolution models against young astrophysical benchmarks and highlight recent progress incorporating non-standard physics, such as magnetic field and starspots, to explain observed deficiencies. While addition of these physical processes leads to improved agreement between models and observations, there are several fundamental limitations in our understanding about how these physical processes operate. These limitations inhibit our ability to form a coherent picture of the essential physics needed to accurately compute young stellar models, but provide rich avenues for further exploration.
Anomalous Spectral Types and Intrinsic Colors of Young Stars
Authors: Pecaut Mark J. 
Published: January 2016

AbstractWe highlight differences in spectral types and intrinsic colors observed in pre-main sequence (pre-MS) stars. Spectral types of pre-MS stars are wavelength-dependent, with near-infrared spectra being 3-5 spectral sub-classes later than the spectral types determined from optical spectra. In addition, the intrinsic colors of young stars differ from that of main-sequence stars at a given spectral type. We caution observers to adopt optical spectral types over near-infrared types, since Hertzsprung-Russell (H-R) diagram positions derived from optical spectral types provide consistency between dynamical masses and theoretical evolutionary tracks. We also urge observers to deredden pre-MS stars with tabulations of intrinsic colors specifically constructed for young stars, since their unreddened colors differ from that of main sequence dwarfs. Otherwise, V-band extinctions as much as ~0.6 mag erroneously higher than the true extinction may result, which would introduce systematic errors in the H-R diagram positions and thus bias the inferred ages.
ALMA and the Future of Millimeter Imaging Observations
Authors: Wilner David J. 
Published: January 2016

AbstractThe Nearby Young Moving Groups sample the critical age when primordial disks around stars complete their transformation into planetary systems with associated debris. Millimeter wavelengths provide direct access to cool material in these circumstellar disks. The high angular resolution of interferometry at these long wavelengths enables resolved observations of solids in an optically thin regime, as well as the thermal, chemical, and dynamical structure of gas, if present. In this contribution, I briefly review the evolving landscape of millimeter telescopes, with emphasis on the revolutionary capabilities of the new international Atacama Large Millimeter/submillimeter Array (ALMA) and describe pertinent early science results.
The Impact of Starspots on Mass and Age Estimates for Pre-main Sequence Stars
Authors: Somers Garrett , Pinsonneault Marc H. 
Published: January 2016

AbstractWe investigate the impact of starspots on the evolution of late-type stars during the pre-main sequence (pre-MS). We find that heavy spot coverage increases the radii of stars by 4–10%, consistent with inflation factors in eclipsing binary systems, and suppresses the rate of pre-MS lithium depletion, leading to a dispersion in zero-age MS Li abundance (comparable to observed spreads) if a range of spot properties exist within clusters from 3-10 Myr. This concordance with data implies that spots induce a range of radii at fixed mass during the pre-MS. These spots decrease the luminosity and Teff of stars, leading to a displacement on the HR diagram. This displacement causes isochrone derived masses and ages to be systematically under-estimated, and can lead to the spurious appearance of an age spread in a co-eval population.
Near-infrared Spectroscopy of Brown Dwarf and Planetary-Mass Members in Upper Scorpius
Authors: Lodieu Nicolas 
Published: January 2016

AbstractIn these proceedings, I present new VLT/X-shooter near-infrared spectroscopy of brown dwarf and planetary-mass candidates with masses below 30 Jupiter masses identified in a deep VISTA ZYJ survey of 13.5 square degrees in the Upper Scorpius (USco) association. These spectra represent new benchmarks at 5–10 Myr to compare with known and future discoveries of members in nearby moving groups and other young regions.
A Pre-Gaia Census of Nearby Stellar Groups
Authors: Mamajek Eric E. 
Published: January 2016

AbstractThe nearest, youngest groups of stars to the Sun provide important samples of age-dated stars for studying circumstellar disk evolution, imaged exoplanets, and brown dwarfs. I briefly comment on the status of the known stellar groups within 100 pc: β Pic, AB Dor, UMa, Car-Near, Tuc-Hor and β Tuc nucleus, Hyades, Col, TW Hya, Car, Coma Ber, 32 Ori, η Cha, and χ1 For. I also discuss some poorly characterized groups and “non-groups.” Grades for 2015 of Pass, Satisfactory, or Fail are assigned to the groups for the purposes of age-dating stars and brown dwarfs. I speculate that Tuc-Hor could have provided a supernova ~60 pc away ~2.2 Myr ago which showered the Earth with traces of 60Fe-bearing dust.
The Age of Taurus: Environmental Effects on Disc Lifetimes
Authors: Rees J. M. , Wilson T. , Bell C. P. M. , Jeffries R. D. , Naylor T. 
Published: January 2016

AbstractUsing semi-empirical isochrones, we find the age of the Taurus star-forming region to be 3-4 Myr. Comparing the disc fraction in Taurus to young massive clusters suggests discs survive longer in this low density environment. We also present a method of photometrically de-reddening young stars using iZJH data.