nils-herrmann/clean_scirepeval huggingface dataset:
Crystallographic evolution of microstructure in thin film processing: Part I. grain size distribution

Processing parameters and the resulting properties of a material are linked by the relationship between processing and microstructure. Characterizing the effect of processing variations on microstructure and determining its origin are essential to advanced material development. In this and a companion article, some readily applied techniques for producing quantitative data on grain size and shape, as well as grain and boundary crystallography, are described. The method described in Part I utilizes transmission electron microscopy and image analysis to measure grain size in large quantities (2000 to 3000 grains per sample), differentiated into orientation class subpopulation distributions. On application to Ni thin films produced by ion assisted deposition, the results have identified an orientation subpopulation that is predominantly responsible for the larger grain sizes observed in films grown under high ion flux. Larger grain size and the development of a preferred orientation have both been associated with increasing ion flux during growth, however, these results give the first experimental evidence connecting grain size and texture in these films.

Field of study: Materials science
Mudflow as a Geologic Agent in Semiarid Mountains

In Utah, Nevada, and other more or less arid parts of the western United States the steeper slopes of most of the mountains are fringed with alluvial deposits, which form bajadas, or alluvial slopes. The unit of a series of such deposits is the alluvial fan, the apex of which is in the mouth of a mountain canyon. The surfaces and the eroded sections of these fans show two features by which they can be distinguished from the alluvial deposits of moister regions: many of the fans are strewn with large, isolated boulders, and the deposit as a whole consists of beds of unassorted and unstratified earthy material, a heterogeneous mixture of particles of all sizes, which in that respect resembles glacial till and some volcanic agglomerates. Lawson2 has given it the convenient name “fanglomerate.” These deposits have generally been supposed to be formed by floods, although floods normally . . .

Field of study: Geology
Rebuttal of Comment on “Radial Dependence of Induced Current Density and Small Pixel Effect in Parallel-Plate Detectors”

Hwang et al., in their “Comment on ‘Radial dependence of induced current density and small pixel effect in parallel-plate detectors”’ argue that my solution to the problem of the charge between two parallel conducting plates is erroneous. In this comment, I shall try to defend my solution for Green’s function and the induced surface charge density.

Field of study: Physics
On the Robustness of Transmit Beamforming

Beamforming is a simple transmit strategy that uses only one eigen-direction in multiple-input multiple-output channels. This simplicity makes beamforming a competitive strategy in practice, but at the same time poses a doubt on the sensitivity of beamforming to the imperfectness of the channel state information at the transmitter (CSIT). This paper studies beamforming from the perspective of worst-case robustness. We show that beamforming can achieve the maximum received signal-to-noise ratio (SNR) or guarantees a given received SNR with the minimum transmit power, in the worst channel within an elliptical uncertainty region defined by the weighted spectral norm. This result further implies that beamforming has the ability to combat against the imperfectness of CSIT, especially for small channel dimensions or small channel uncertainty.

Field of study: Engineering
Facile Preparation and Chemical Transformations of Spirocyclopropane‐Annelated Heterocycles

A productive approach has been developed to spirocyclopropane-annelated 1,4-benzoxathiane 17 (85%), 1,4-benzothiazines 20−22 (56−88%) and 1,4-benzoxazines 25, 26 (55−71%), through Michael additions of binucleophilic o-hydroxythiophenol 15, o-aminothiophenols 8 and o-hydroxysulfanilides 23 onto methyl and tert-butyl 2-chloro-2-cyclopropylideneacetates (1-Me, 1-tBu), followed by ring closure in the intermediate of type 3 through nucleophilic substitution of the chlorine atom and, in the case of the intermediates 20, 21 and 25, elimination of benzenesulfinic acid. Reduction of 20a with LiAlH4 led to the hydroxymethyl derivative 28 (88%) with retention of the N-phenylsulfonyl group, while that of the oxazinecarboxylate 26a-Me gave the β-amino alcohol 27 (87%). Selective reduction of the C=N double bond in 26a-Me was achieved with NaBH4 in methanol. Halogen-substituted benzoxazines 26b,c were modified further by Heck coupling with various alkenes. In the presence of a catalytic amount of triphenylphosphane, only the 6-bromobenzoxazine underwent Heck coupling accompanied by ring opening of the spirocyclopropane moiety. The best yields of cross-coupling products 30d−i (60−89%) retaining the spirocyclopropane ring were achieved for 6-iodobenzoxazine 26c-Me reacting with methyl acrylate, acrolein, and methyl vinyl ketone, respectively. By treatment with morpholine in DMF, the heterocyclic esters 26b,c undergo demethoxycarbonylation to form spirocyclopropane-annelated 1,4-benzoxazines 36b,c in high yields (83−98%). The 1,4-benzoxazine 36b readily adds nucleophiles such as p-thiocresol and hydrogen cyanide across its C=N double bond to yield compounds 37 (76%) and 38 (95%), respectively.

Field of study: Chemistry
Expressing casual relationships in conceptual database schemas

Conceptual schema design is a crucial phase in the database design process. The quality of the final database (regardless of logical implementation model) is dependent largely upon the quality of the conceptual schema. Since conceptual schemas serve as formal representations of the requirements specification for a database, it is critical that a schema capture the requirements as completely and unambiguously as possible. Many studies have shown that semantic models, such as the Extended Entity–Relationship model, are better for conceptual database design than traditional models such as relational, hierarchical, and network models. This is primarily because of their ability to capture explicitly many “natural” cognitive relationship types that are likely to occur in requirements specifications, e.g., association, generalization/specialization, and aggregation. However, the relationships that can be specified in a semantic model represent only a subset of the relationships that are likely to be used by people in describing an application environment. Thus, using current semantic models for conceptual database design may result in abstractions of application environments in which some important information from the requirements is either not represented or is represented inappropriately.This paper seeks to help bridge the gap between requirements specifications and data modeling by hypothesizing the need for supporting additional cognitive relationship types in conceptual models. In the paper, we demonstrate the need for one such relationship type, causation. Specifically, we investigate the effects of the lack of constructs in semantic models for capturing causation on analysts' ability to express causal relationships mentioned in a requirements document.We found that subjects not familiar with data modeling expressed causal relationships better in their representations than did subjects who had some prior exposure to data modeling. This seems to indicate that the lack of constructs for capturing causation in semantic models hinders the ability of people trained in data modeling techniques to recognize and express causal relationships in conceptual schemas. The results also suggest the need to develop semantic models that provide constructs for capturing causation and other cognitive relationships.

Field of study: Computer science, Engineering
Early stall of West Antarctic Ice Sheet advance on the eastern Ross Sea middle shelf followed by retreat at 27,50014CyrBP

Marine geological and geophysical data suggest that the West Antarctic Ice Sheet (WAIS) deposited three thick seismically-resolvable units in the eastern Ross Sea since the Last Glacial Maximum (LGM) but the chronology of these grounding events is debated. Existing ice-retreat chronologies for the eastern Ross Sea are considered suspect because nearly all have been developed using radiocarbon dating of acid-insoluble organics (AIO) from bulk sediment. We used a new strategy to isolate in situ forams from diamict sediment deposited at the middle-shelf grounding-zone wedge (GZW) — a subaqueous ice-marginal landform previously interpreted to represent deposition during the third grounding event since the LGM advance to the shelf edge. Here we present a synthesis of our new radiocarbon dates of foram tests and AIO with previously published radiocarbon dates. We propose that the WAIS's LGM advance in the eastern-Ross Sea sector reached the middle shelf circa 27,500 14C yr BP and that open-marine sedimentation began shortly thereafter. There is as of yet no clear explanation for why WAIS retreat in this sector of Antarctica apparently began prior to the peak of the last glacial cold period. A precipitation deficit, localized warm water intrusion, an ice dynamic response in the absence of climate forcing or another as of yet unknown forcing mechanism could be responsible.

Field of study: Environmental science, Geography
SGor: Trust graph based onion routing

The use of trust for onion routing has been proved effective in thwarting malicious onion routers. However, even state-of-the-art trust-based onion routing protocols still suffer from two key limitations in protecting anonymity. First, these protocols have no means to verify the correctness of the trust they rely on. Second, they run a high risk of being deanonymized by an inference attack due to biased trust distributions. In this paper, we propose SGor, a trus tg raph based onion routing that mitigates the key limitations of trust in protecting anonymity. SGor is novel with three unique properties. First, SGor aggregates group trust from mutual friends to verify the correctness of users’ trust assignments. Second, SGor employs an adaptive trust propagation algorithm to derive global trust from trust graph. The global trust removes the restriction of users’ local knowledge and defeats inference attacks by guiding users to discover and trust more honest routers (i.e., reducing the bias of trust distribution). Third, SGor is designed to operate in a fully decentralized manner. This decentralized design mitigates the leakage of a priori trust relationships. We evaluate SGor with simulation-based experiments using several real-world social trust datasets. The experimental results confirm that SGor can mitigate key limitations in the use of trust for protecting anonymity but introduces only a few overheads.

Field of study: Computer science
Theoretical study on two beams interactions in cylindrical waveguide filled with plasma

The interaction of two electron beams in a cylindrical waveguide filled with plasma is studied in this paper.The linear theory is established based on a fluid model.The numerical results show the two-stream instability of two electron beams can produce Cherenkov radiation through the interaction between the fast space charge wave and the slow space charge wave,and the frequency of radiation can be above the plasma frequency.When the plasma frequency exceeds the frequency scope of the interaction,the interactions of beam-plasma and beam-beam can be improved and enhanced greatly.

Field of study: Physics
Development of a Genomic Resource and Identification of Nucleotide Diversity of Yellow Perch by RAD Sequencing

Yellow perch (Perca favescens) is an important native North American fish in ecology and aquaculture. However, molecular markers are minimal for this species, especially those with genome-wide distribution. Single sequence repeat markers are always developed based on sequences from a single individual, which is time consuming with a low success rate. In this study, combining data from HiSeq and MiSeq platforms, we applied restriction site-associated DNA sequencing (RAD-Seq) to yellow perch geographic demes to develop large numbers of polymorphic genetic markers, including single nucleotide polymorphisms and simple sequence repeats, and to evaluate nucleotide diversity. A total of 258,056 contigs were assembled with the length of 605 ± 71 (mean ± SD) bp, which were longer than those just using HiSeq data. Nucleotide diversity (π) was 0.00304 with 95% confidence intervals from 0.00303 to 0.00304. Based on the assembled sequences, a total of 59,766 perfect single sequence repeats were detected, with AC/GT being the most common repeat motif and GC being the rarest. Based on this breeding population, 41,736 high-quality single nucleotide polymorphisms and 10,412 polymorphic single sequence repeats were obtained. Validation of amplification by randomly selecting 40 polymorphic single sequence repeats showed a high success rate (85%). Our approach for polymorphic single sequence repeats development enables new usage of data from RAD-seq techniques. These developed markers could be used in finfish broodstock management, genetic improvement and resource conservation, and would contribute to sustainable development of fisheries and the aquaculture industries.

Field of study: Biology
Multi-Objective Scheduling for Space Science Missions

We have developed an architecture called MUSE (MultiUser Scheduling Environment) to enable the integration of multiobjective evolutionary algorithms with existing domain planning and scheduling tools. Our approach is intended to make it possible to re-use existing software, while obtaining the advantages of multi-objective optimization algorithms. This approach enables multiple participants to actively engage in the optimization process, each representing one or more objectives in the optimization problem. As initial applications, we apply our approach to scheduling the James Webb Space Telescope, where three objectives are modeled: minimizing wasted time, minimizing the number of observations that miss their last planning opportunity in a year, and minimizing the (vector) build up of angular momentum that would necessitate the use of mission critical propellant to dump the momentum. As a second application area, we model aspects of the Cassini science planning process, including the trade-off between collecting data (subject to onboard recorder capacity) and transmitting saved data to Earth. A third mission application is that of scheduling the Cluster 4-spacecraft constellation plasma experiment. In this paper we describe our overall architecture and our adaptations for these different application domains. We also describe our plans for applying this approach to other science mission planning and scheduling problems in the future.

Field of study: Computer science
Dynamic sub-grid scale turbulent Schmidt number approach in large eddy simulation of dispersion around an isolated cubical building

In this paper, the effects of the sub-grid scale (SGS) turbulent Schmidt number, ScSGS, on the large eddy simulation of dispersion on and around an isolated cubical model building with a flush vent located on its roof are examined. Constant and dynamic ScSGS approaches for SGS turbulent mass flux modeling are employed. Simulation results are compared with the available wind tunnel measurements. Furthermore, the influence of the grid resolution on the accuracy of results predicted by the dynamic ScSGS approach is investigated. Detailed statistical analysis of ScSGS demonstrates that the dynamically computed ScSGS at different locations varies by a factor of almost 5 and a considerable deviation of ScSGS from its common values of 0.5 and 0.7 occurs. Particularly, in the vicinity of the building where the concentration gradients are noticeable, ScSGS has a larger variation. Also, the probability of occurrence of 0.2 < ScSGS <1.5 is more than 90 percent and the ScSGS mean values are nearly around 0.8 to 1 with a maximum variance of 0.2. In addition, by refining the grid, the differences between the predictions of constant and dynamic ScSGS approaches decrease. This is due to the reduction of sub-grid scales contribution to turbulent dispersion. It is confirmed that dynamic ScSGS approach is a practical alternative to the constant ScSGS approach, effectively eliminating a user-defined model coefficient.

Field of study: Engineering
Midwave-infrared negative luminescence properties of HgCdTe devices on silicon substrates

We have investigated the negative luminescence properties of a midwave-infrared (MWIR) HgCdTe photodiode (λco = 5.3 µm at 295 K) grown on a silicon substrate. The internal negative luminescence efficiencies measured using a self-referencing optical technique were 88% throughout the 3–5 µm spectral region and nearly independent of temperature in the 240–300 K range. This corresponds to an apparent temperature reduction of 53 K at room temperature and 35 K at 240 K. Efficiencies measured by an electrical modulation technique were consistent with the measured internal efficiencies and the measured reflectivity of the device. This is the highest efficiency and largest apparent reduction in temperature reported to date, and slightly higher than that measured earlier for photodiodes grown on CdZnTe despite a longer cut-off wavelength. These results provide further indication that the HgCdTe/Si photovoltaic device technology is capable of combining high quality with high yield.

Field of study: Materials science
Zircon U-Pb ages from the Wabigoon-Manitou Lakes region, Wabigoon Subprovince, northwest Ontario

Three distinct stratigraphic units have been recognized in the Crow Lake – Savant Lake belt. These are a basal unit consisting of high magnesium tholeiitic flows, a middle unit consisting mostly of tholeiitic to calc-alkaline pyroclastic rocks and flows, and an upper unit of high iron tholeiitic flows.A zircon U–Pb study has been carried out on seven rocks from the Wabigoon–Manitou Lakes region of this belt. In the Manitou Lakes area, a minimum age of 2755 Ma on a porphyry pluton intruded into the Wapageisi Volcanics gives a minimum age for the high magnesium tholeiitic sequence.A trondhjemite phase of the Atikwa batholith near Wabigoon Lake that is dated at 2732.2 ± 2.9 Ma has the same age within experimental error as a rhyolite flow from the Lower Wabigoon Volcanics in the same area that is dated at . However, a trondhjemite phase of the Atikwa batholith at Eagle Lake that is dated at is distinctly younger than a dacite flow collected nearby from the Lower Wabigoon Volcanics that is dated at . Both thes...

Field of study: Environmental science
Loss of Ref-1 protein expression precedes DNA fragmentation in apoptotic neurons.

Ref-1 is a bifunctional protein that has been implicated in the transcriptional regulation of AP-1 elements and in DNA repair. To investigate whether Ref-1 is involved in programmed cell death its expression was measured in the 21-day-old rat brain at various time-points following a moderate unilateral hypoxic-ischemic (HI) insult. The CA1 pyramidal cells, which are selectively vulnerable to HI injury, showed a significant decrease in Ref-1 immunoreactivity 48 h-7 days post-insult. This loss of Ref-1 immunoreactivity may contribute to a decrease in endogenous repair activity and the development of apoptosis in the CA1 pyramidal cells.

Field of study: Biology
The theoretical significance of Universal Grammar in second language acquisition

The evidence that native language acquisition is possible only because children are born with an innately-determined language faculty - Universal Grammar - is considerable. The evidence that the same innate ability is involved in second language acquisition (SLA) by older learners is superficially less clear. There are differences both in the context of acquisition and the nature of development. One recent approach suggests that only ‘poverty of the stimulus’ phenomena - where neither the first language (L1) nor the second language (L2) are possible sources for L2 representations - can provide incontrovertible evidence for Universal Grammar (UG) in SLA. I argue that while ‘poverty of the stimulus’ phenomena are important landmarks in theory development in SLA research, they are not the most compelling reason for assuming the involvement of UG. More compelling are attempts to explain L2-L1 differences. The latter are likely to lead to real progress, not only in understanding the nature of SLA but also the structure and organization of the language faculty itself.

Field of study: Linguistics
SYNTHESIS OF SOME ALKALOIDS USING THE ALLYL DERIVATIVES OF BORON

Data on the application of the allylic derivatives of boron for the synthesis of piperidine, indolizine, pyrrolizidine, and indole alkaloids are reviewed.  Translation in Chemistry of Heterocyclic Compounds , 1999, 35 (8), pp 888-899 http://link.springer.com/article/10.1007/BF02252156

Field of study: Chemistry
Surveillance video synopsis generation method via keeping important relationship among objects

To reduce the efforts of human in browsing long surveillance videos, synopsis videos are proposed. Traditional synopsis video generation methods condense most of the activities in the video by simultaneously showing several actions, even when they originally occurred at different times. This inevitably causes ignorance of temporal relationship among objects. For example, two persons walk shoulder to shoulder and they are detected and tracked separately, but in the synopsis they never ‘met’. In this study, a trajectory mapping model is defined, whose energy function includes not only the cost caused by the synopsis video, but that of the original video. In this way, it tries to make the relationship between objects of the original video consistent with that of the synopsis. Finally, the video synopsis is generated by an energy minimisation method. Experiments show that the proposed video synopsis can reduce the spatiotemporal redundancies of the input video as much as possible. Moreover, it can keep the important relationship between objects and maintain the time consistency of important activities.

Field of study: Computer science
Optimization-based non-cooperative spacecraft pose estimation using stereo cameras during proximity operations.

Pose estimation for spacecraft is widely recognized as an important technology for space applications. Many space missions require accurate relative pose between the chaser and the target spacecraft. Stereo-vision is a usual mean to estimate the pose of non-cooperative targets during proximity operations. However, the uncertainty of stereo-vision measurement is still an outstanding issue that needs to be solved. With binocular structure and the geometric structure of the object, we present a robust pose estimation method for non-cooperative spacecraft. Because the solar panel can provide strict geometry constraints, our approach takes the corner points of which as features. After stereo matching, an optimization-based method is proposed to estimate the relative pose between the two spacecraft. Simulation results show that our method improves the precision and robustness of pose estimation. Our system improves the performance with maximum 3D localization error less than 5% and relative rotation angle error less than 1°. Our laboratory experiments further validate the method.

Field of study: Physics