bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optical, structural, and magnetic properties of p‐type GaN implanted with Fe+ (5 and 10 at%)
Authors: Shon Yoon , Park Young S. , Lee Seejoon , Jeon H. C. , Kwon Y. H. , Kang T. W. , Kim Jin Soak , Kim Eun Kyu , Kim C. K. , Yoon C. S. 
Published: December 2006

Abstractp‐type GaN epilayers were prepared by metalorganic chemical vapor deposition and subsequently implanted with Fe+. The results of energy dispersive X‐ray peak displayed the Fe‐injected concentration of 5 and 10 at%, respectively. The results of photoluminescence measurement show that optical transitions related to Fe appear at 2.5 and 3.1 eV. It was confirmed that the photoluminescence peak at 2.5 eV is a donor‐Fe acceptor transition and the photoluminescence peak at 3.1 eV is a conduction band‐Fe acceptor transition. Apparent ferromagnetic hysteresis loops measured at 10 and 300 K with the Fe concentration of 10 at% were observed, and the temperature‐dependent magnetization displayed a ferromagnetic behavior persisting up to 300 K. The systematic enhancement of ferromagnetic hysteresis loops for GaN implanted with high doses of Fe (5 → 10 at%) takes place with an increase in the annealing temperature from 700 to 850 °C. The trends of magnetic properties coincide with the results of the increased full width at half maximum of triple axis diffraction for GaN (0002) including the appearance of GaFeN, the enhanced Fe‐related photoluminescence transitions, and the increased sizes of symmetric spin ferromagnetic domains GaFeN in atomic force microscopy and magnetic force microscopy systematically. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photoluminescence and Hall studies of GaN:Fe and (Ga,Fe)N:Mg layers
Authors: Wegscheider M. , Simbrunner C. , Przybylińska H. , Kiecana M. , Sawicki M. , Navarro‐Quezada A. , Sitter H. , Jantsch W. , Dietl T. , Bonanni A. 
Published: December 2006

AbstractTemperature dependent photoluminescence (PL) in the ultraviolet (UV) regime and Hall measurements at room temperature have been performed on Metal‐Organic‐Chemical‐Vapour‐Deposition (MOCVD) grown GaN:Fe and (Ga,Fe)N:Mg layers. PL measurements were employed in order to study the dopants' influence on the near‐band edge excitonic emission and their tendency to provoke the formation and suppression of defects or incorporation of impurities. For their identification and for the understanding of the PL spectra the evaluation of the free carrier concentrations via Hall measurements were necessary. Depending on the iron concentration of the (Ga,Fe)N layers, the near‐band edge emission goes through two different stages: at low Fe‐concentration no excitonic emission can be seen whereas with higher doping levels, excitonic features develop. The (Ga,Fe)N films exhibit n‐type behaviour. The Mg codoped samples show strong Mg and defect related luminescence bands, whose occurrence and intensity also strongly depends on whether high or low Fe concentration is present. The (Ga,Fe)N:Mg layers were semi insulating. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Defects in thin film silicon at the transition from amorphous to microcrystalline structure
Authors: Astakhov O. , Carius R. , Petrusenko Yu. , Borysenko V. , Barankov D. , Finger F. 
Published: December 2006

AbstractDefects in thin film silicon with different structure all the way from amorphous to microcrystalline were investigated by electron spin resonance with emphasis on amorphous material prepared close to the transition to crystalline growth. Electron beam irradiation and stepwise annealing is used for reversible variation of the defect density over three orders of magnitude. The electron irradiation enhances mainly the native paramagnetic defects. Additional resonances are found as satellites to the central line, which anneal rapidly at temperatures below 100 °C. These features are most pronounced for the amorphous material prepared close to the transition to crystalline growth. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Surface morphology of highly mismatched InSb films grown on GaAs substrates by molecular beam epitaxy
Authors: Xiong Min , Li Meicheng , Zhao Liancheng 
Published: December 2006

AbstractInSb films on GaAs(001) substrates with and without GaAs buffer layer have been grown by molecular beam epitaxy. Rather than surface undulations, aligned ripples and pyramidal hillocks along the orthogonal 〈110〉 directions were observed on the surface of InSb films. Both the preferential growth and the termination of ripples were proved to be related to strain‐driven mass transport. A model was proposed to elucidate the formation of the hillocks, which are more efficient to relax strain than ripples. Due to the strain relaxation through hillocks with small bases predominantly, the surfaces of the InSb films grown without a GaAs buffer layer are smoother than those of films grown with a GaAs buffer layer. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Beyond cost models: communications satellite revenue models. Integrating cost considerations into a value‐centric mindset
Authors: Saleh J. H. , Torres Padilla J. P. 
Published: December 2006

AbstractWhile satellite cost models are pervasive throughout the aerospace industry, revenue models or utility models of space systems are quasi‐inexistent. This situation perhaps conveys the false impression that satellites are either cost sinks or expensive artefacts whose value or utility profile over their design lifetime is difficult to quantify. In this paper, we propose that satellites, like any other complex engineering systems, should be perceived as value delivery artefacts, and the value delivered, or the flow of service that the spacecraft delivers over its design lifetime, deserves as much effort to quantify as the system's cost. To this effect, we build, in the case of a GEO communications satellite, revenue models based on (1) statistical analyses of spacecraft loading dynamics and (2) historical trends of market prices for the communications services provided. Results and discussions presented here should prove useful to satellite operators and industry observers. Copyright © 2006 John Wiley & Sons, Ltd.
Improved TDM switching assignments for variable and fixed burst length
Authors: Kagaris Dimitri 
Published: December 2006

AbstractIn this paper we present two algorithms for improved satellite‐switched TDM slot assignments ofN×Ntraffic matrices underKtransponders/carriers (simultaneous connections), 1⩽K⩽N. The first algorithm applies to data switching with variable burst length and achieves optimum transmission time with a significantly lower number of switching configurations than a previously proposed algorithm, while still having the same time complexity (O(N4)). Experimental results demonstrate the advantage. The second algorithm applies to the case of fixed burst length and offers a faster complexity ofO(L·N2), whereLis the minimum transmission time, at the cost of occasionally missing the minimum. Extensive simulations indicate that the difference from the minimum is rare and is at most one. They also show that the presented algorithm even improves a previous one which was proposed for the fixed burst length case and has the same time complexity but usesK=N. Copyright © 2006 John Wiley & Sons, Ltd.
Locating faulty code by multiple points slicing
Authors: Zhang Xiangyu , Gupta Neelam , Gupta Rajiv 
Published: December 2006

AbstractDynamic slicing has long been considered as a useful tool for debugging programs as it effectively identifies a reduced fault candidate set which captures the faulty code in the program. Traditionally, a backward dynamic slice is computed starting from an incorrect value observed by the programmer during a failed program run. This incorrect value is either an incorrect output value or an incorrect address whose dereferencing causes the program to crash. Recently we proposed two additional types of dynamic slices, a forward dynamic slice of a minimal failure inducing input difference and a bidirectional dynamic slice of a critical predicate. We have built a dynamic slicing tool that computes dynamic slices by instrumenting program binaries and executing them to build dynamic dependence graphs. In this paper, through experiments, we demonstrate that supporting three different types of dynamic slices has the following advantages. First, we observe that for each type of dynamic slice there are distinct situations in which it is not applicable. Therefore, we should support multiple types of slices to handle a wide range of situations. Second, supporting multiple types of dynamic slices enables us to compute a multiple points dynamic slice which is the intersection of different type of available slices. Our experiments show that multiple points dynamic slices are significantly smaller than any of the three kinds of individual dynamic slices. Copyright © 2006 John Wiley & Sons, Ltd.
Systematic pattern selection using pattern language grammars and design space analysis
Authors: Zdun Uwe 
Published: December 2006

AbstractSoftware patterns provide reusable solutions to recurring design problems in a particular context. The software architect or designer must find the relevant patterns and pattern languages that need to be considered, and select the appropriate patterns, as well as the best order to apply them. If the patterns and pattern languages are written by multiple pattern authors, it might be necessary to identify interdependencies and overlaps between these patterns and pattern languages first. Out of the possible multitude of patterns and pattern combinations that might provide a solution to a particular design problem, one fitting solution must be selected. This can only be mastered with a sufficient expertise for both the relevant patterns and the domain in which they are applied. To remedy these issues we provide an approach to support the selection of patterns based on desired quality attributes and systematic design decisions based on patterns. We propose to formalize the pattern relationships in a pattern language grammar and to annotate the grammar with effects on quality goals. In a second step, complex design decisions are analyzed further using the design spaces covered by a set of related software patterns. This approach helps to systematically find and categorize the appropriate software patterns—possibly even from different sources. As a case study of our approach, we analyze patterns from a pattern language for distributed object middleware. Copyright © 2006 John Wiley & Sons, Ltd.
Significance of severe distant and moderate close earthquakes on design and behavior of tall buildings
Authors: Mwafy Aman , Elnashai Amr , Sigbjörnsson Ragnar , Salama Assaad 
Published: December 2006

AbstractMany sites around the world may be subjected to severe distant earthquakes alongside moderate‐size, short source‐to‐site distance events. The two scenarios have different impacts on high‐rise buildings and should be therefore investigated. Dubai, a region with an exceptionally high rate of development, is vulnerable to the aforementioned earthquake hazard scenarios. The region represents one of the most rapidly growing in construction of tall buildings worldwide. It was therefore selected for the investigation described in the paper. A hazard study for the construction site of a 187m high reinforced concrete tower is conducted. Seismicity of the region is outlined and a hazard assessment is carried out to evaluate peak ground accelerations and uniform hazard spectra for different probabilities of exceedance. A number of natural and synthetic records are selected to represent different seismic assessment scenarios at the site. The RC tower is then modeled and analyzed using state‐of‐the art analytical platforms. Three‐dimensional elastic, inelastic pushover and response history analyses are carried out to verify the dynamic characteristic and estimate the capacity to compare it with the predicted demand. The significance of including severe distant earthquakes in design and assessment of high‐rise buildings is confirmed. Records representing the latter scenario amplify the fundamental mode that may be overlooked in design using short source‐to‐site earthquakes. A proposal is made for scaling the results from inelastic dynamic analysis to arrive at a safe and economical design level. The study not only presents comprehensive hazard and vulnerability study for the selected test case, but also gives conclusions that generically apply to the class of long‐period buildings subjected to large‐distant and small‐close earthquakes. Copyright © 2006 John Wiley & Sons, Ltd.
On the shear strength of reinforced concrete deep beam with web opening
Authors: Eun Hee‐Chang , Lee Young‐Ho , Chung Heon‐Soo , Yang Keun‐Hyeok 
Published: December 2006

AbstractAn objective of this study is to establish the shear strength of reinforced concrete deep beam with web opening. Eighteen beams were tested with the variables of the steel ratio and strength of longitudinal bars, concrete strength, and shear span‐to‐depth ratio. It was observed that the opening is strengthened by longitudinal bars but the load‐carrying capacity of deep beams with openings can be largely improved by the increase in concrete strength. Modifying the softened truss model derived by Mau and Hsu and utilizing the results of this experiment carried out with the variables of concrete strength, cross‐section size, shear‐span‐to‐depth ratio, and the strength and steel ratio of longitudinal bars, this study proposes an improved model to predict the shear strength. Copyright © 2006 John Wiley & Sons, Ltd.
Prenatal detection and outcome of congenital diaphragmatic hernia: a French registry‐based study
Authors: Gallot D. , Boda C. , Ughetto S. , Perthus I. , Robert‐Gnansia E. , Francannet C. , Laurichesse‐Delmas H. , Jani J. , Coste K. , Deprest J. , Labbe A. , Sapin V. , Lemery D. 
Published: December 2006

AbstractObjectivesTo describe the true incidence, prenatal detection rate and fetal outcome of congenital diaphragmatic hernia (CDH) in a systematically registered population over an 18‐year period and to determine any change in trends over time.MethodsThis was a retrospective study of all cases of CDH registered in the Central‐Eastern France Birth Defects Registry from 1986 to 2003. All fetuses and infants up to 1 year of age diagnosed with CDH were registered, including miscarriages later than 22 weeks of gestation, stillbirths and terminations of pregnancy (TOP). Routine prenatal screening consisted of three ultrasound examinations and there was no upper limit of gestational age for TOP.ResultsFive hundred and one cases of CDH were identified from a total of 1 835 022 live births (2.7 cases per 10 000 live births). The overall prenatal detection rate was 54%. There was a significant increase over time in the detection rate mainly for associated CDH and left‐sided CDH (P < 0.0001), and in the proportion of neonates delivered in tertiary centers (P < 0.0001). The overall survival rate at discharge was 47% and this increased significantly over time for isolated CDH (P = 0.04), whereas it was lower and remained stable for associated CDH (P = 0.64). The TOP rate for isolated CDH did not vary significantly in contrast to that for associated CDH cases in which the TOP rate increased over time, progressively replacing the neonatal death rate (P = 0.01).ConclusionsOver an 18‐year period, this large population‐based study demonstrated increasing prenatal detection rates for associated CDH and left‐sided CDH and confirmed an increasing survival rate mainly for isolated CDH. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Diagnostic Sensitivity of Contrast Swallow for Leakage after Gastric Resection
Authors: Tonouchi Hitoshi , Mohri Yasuhiko , Tanaka Kouji , Ohi Masaki , Kobayashi Minako , Yamakado Koichiro , Kusunoki Masato 
Published: December 2006

AbstractIntroductionWe examined the clinical manifestations and computed tomography findings of patients with leakage after gastrectomy for cancer and determined the sensitivity of the contrast swallow for the leakage diagnosis.MethodsThe medical records of 331 consecutive patients undergoing gastrectomy between January 1992 and December 2003 were reviewed. Routine contrast swallow was performed in all patients before oral intake. Once leakage was suspected, an emergency contrast swallow was performed and its diagnostic sensitivity determined.ResultsIn total, leakage was diagnosed 9 of 17 times by the contrast swallow, for a diagnostic sensitivity of 53%. The clinical signs or another imaging modality often corrected the misdiagnosis.ConclusionsThe diagnostic sensitivity of contrast swallow for leakage after gastrectomy was low. Therefore, if we employ the contrast swallow technique, we should keep in mind its low sensitivity.
A Propensity Score Adjustment for Multiple Group Structural Equation Modeling
Authors: Hoshino Takahiro , Kurata Hiroshi , Shigemasu Kazuo 
Published: December 2006

In the behavioral and social sciences, quasi-experimental and observational studies are used due to the difficulty achieving a random assignment. However, the estimation of differences between groups in observational studies frequently suffers from bias due to differences in the distributions of covariates. To estimate average treatment effects when the treatment variable is binary, Rosenbaum and Rubin (1983a) proposed adjustment methods for pretreatment variables using the propensity score.However, these studies were interested only in estimating the average causal effect and/or marginal means. In the behavioral and social sciences, a general estimation method is required to estimate parameters in multiple group structural equation modeling where the differences of covariates are adjusted.We show that a Horvitz-Thompson-type estimator, propensity score weighted M estimator (PWME) is consistent, even when we use estimated propensity scores, and the asymptotic variance of the PWME is shown to be less than that with true propensity scores.Furthermore, we show that the asymptotic distribution of the propensity score weighted statistic under a null hypothesis is a weighted sum of independent χ12
variables.We show the method can compare latent variable means with covariates adjusted using propensity scores, which was not feasible by previous methods. We also apply the proposed method for correlated longitudinal binary responses with informative dropout using data from the Longitudinal Study of Aging (LSOA). The results of a simulation study indicate that the proposed estimation method is more robust than the maximum likelihood (ML) estimation method, in that PWME does not require the knowledge of the relationships among dependent variables and covariates.
Phase diagram of α‐sulfonate methyl esters derived from palm stearin/alcohol/water systems
Authors: Lim Wen Huei 
Published: December 2006

AbstractPhase diagrams of α‐sulfonate methyl ester derived from palm stearin (α‐SMEPS)/alcohol/water systems were mapped at 30±0.1°C. Two main regions—an isotropic and a lamellar liquid crystalline—were the focal points in this system. An increase in alcohol chain length decreased the isotropic region and increased the lamellar liquid crystal region. In the isotropic region, self‐assembly of α‐SMEPS at different alcohol chain lengths was determined by using conductivity and viscosity measurements. The phase boundaries of micelle to bicontinuous structure and bicontinuous structure to inverse micelle transitions in the isotropic regions are proposed from these analytical methods. The increase in alcohol chain length shifted the micelle ⇆ bicontinuous structure to the water‐rich corner, and the bicontinuous structure ⇆ inverse micelle transition moved toward the alcohol‐rich corner.
The effect of some foam boosters on the foamability and foam stability of anionic systems
Authors: Sakai Takaya , Kaneko Youhei 
Published: December 2006

AbstractThe foaming properties of anionic surfactant solutions containing a nonionic surfactant, fatty acid N‐methyl‐ethanolamide (NMEA), were investigated. Foamability, which is the foam‐generating power at the initial stage of foaming, was measured by a laboratory‐built foam‐testing apparatus, and also by the conventional Ross‐Miles test NMEA synergistically increased the foamability of anionic surfactant solutions, particularly when small amounts of NMEA were added. Shorter hydrocarbon chain lengths of NMEA, such as N‐octanoyl‐N‐methylethanol (NMEA‐08) and N‐decanoyl‐N‐methylethanol (NMEA‐10), showed better performance in the laboratory‐built foam tester. The results of the Ross‐Miles evaluation, however, were completely opposite. Compared with commercial nonionic boosters, such as fatty acid monoethanolamide, fatty acid diethanolamide, and lauramidopropyldimethylbetaine (LPB), NMEA was the most effective for increasing foamability of the solution at the initial stage. The most popular amphoteric foam booster, LPB, did not increase foamability but likely generated the initial foam volume on the Ross‐Miles test as a result of foam film stabilization. From these results, a foam‐boosting mechanism of NMEA different from that of LPB is suggested.
Investigation of the properties of decaoxyethylene n‐dodecyl ether, C12E10, in the aqueous sugar‐rich region
Authors: Sharma K. Shivaji , Rakshit Animesh Kumar 
Published: December 2006

AbstractInterfacial, thermodynamic, and morphological properties of decaoxyethylene n‐dodecylether [CH3 (CH2)11(OCH2CH2)10OH](C12E10) in aqueous solution were analyzed by tensiometric, viscometric, proton nuclear magnetic resonance (NMR), and small‐angle neutron scattering (SANS) techniques. Dynamic and structural aspects at different temperatures in the absence and presence of sugars at different concentrations were measured. Critical micelle concentrations (CMC) were determined by surface tension measurements in the presence of ribose, glucose, and sucrose. The heat capacity (ΔCp.m.), transfer enthalpy (ΔHm.tr.), transfer heat capacities (ΔCp.m.tr.), micellization constant (Km), Setchenow constant (KSN), and partition coefficient (q) were determined and discussed as an extension of the usual thermodynamic quantities of micellization and adsorption at the air‐water interface. An enthalpy‐entropy compensation effect was observed with an isostructural temperature (Tc) of about 310 K for both micellization and interfacial adsorption. SANS measurements were taken to elucidate structural information, viz., aggregation number (Nagg), shape, size, and number density (Nm) on C12E10 micelles in D2O at different concentrations of sugars (0.05, 0.02, 0.3, and 0.5 M) and temperatures (30, 45, and 60°C). Intrinsic viscosity gave the hydrated micellar volume (Vh), volume of the hydrocarbon core (Vc), and volume of the palisade layer of the oxyethylene (OE) unit (VOE). SANS, as well as rheological data, supported the formation of nonspherical micelles with or without sugars. By SANS, we also observed that at the studied temperature intervals, oblate ellipsoid micelles changed into prolate ellipsoids and the number density of micelles decreased with an increase in temperature both in the presence and in the absence of sugars and also on increasing the concentration of sugars. Proton NMR showed a change in chemical shift of the OE group of micelles above the CMC. We also studied the phase separation of C12E10 by sugars in cloud point measurements.