bluuebunny/crossref_metadata_2025_split huggingface dataset:
CNC Planing Process for Turbine Twisted Blade Profile
Authors: Ding Tao , Li Jia , Jin Yongquan , Zhang Juncheng 
Published: December 2019

Abstract
In this paper, a multi-axis follow-up CNC planing process for twisted blade profile is proposed to reduce the machining cost and achieve high machining efficiency. Firstly, the planing process of the turbine twisted blade is analysed to determine the planing shaping movements; then the machine layout and CNC planing system needed to realize the shaping movements are constructed; then the implementation method of the multi-axis follow-up function which is unique to the CNC planing system is studied; Finally, a proof experiment of this machining process has been done to verify its feasibility.
The Microstructural Evolution of a Cold Rolled AlSi9Mg Aluminum Alloy after Semi-Solid Isothermal Treatment Process
Authors: Wang Yongfei , Zhao Shengdun , Guo Yi , Li Shuangjiang , Fan Xiaoguang 
Published: December 2019

Abstract
The key factor in semi-solid metal forming process is the preparation of semi-solid billet with fine and spherical microstructure. The recrystallization and partial melting (RAP) process consists of cold deformation and semi-solid isothermal treatment (SSIT) is a promising method, because that many alloys are always supplied in the deformed state. In this work, a cold rolled AlSi9Mg aluminum alloy was used directly to fabricate semi-solid billets. During the RAP process, samples cut from the cold rolled AlSi9Mg aluminum alloy were treated with different isothermal holding temperatures and times, and the effects of isothermal treatment parameters on the microstructures of AlSi9Mg alloy semi-solid billets were investigated. The results show that, with increasing the isothemal holding temperature and time, the average grain size of solid grains is gradually increased, the spheroidization degrees of solid grains are sharply increased and then follows by a slight improvement. The high-quality semi-solid billets can be prepared with SSIT process at 570 °C for 5~10 min.
Prediction of a residual operating life of engines
Authors: Bazhenov Y , Bazhenov M 
Published: December 2019

Abstract
Results of the executed researches on prediction of an individual residual operating life of engines are pre-sented in article. Prediction is based on the diagnostic information on technical condition of engines ob-tained during the carrying out their maintenance and repair. The analytical equation, the describing regu-larities of change of diagnostic parameters on an operating time and its graphic interpretation are given. The forecasting technique of a residual operating life of mechanisms of engines with use of the lower fidu-cial bound of distribution of their practices to the limiting condition is offered. The technique is approved on the example of forecasting of a residual operating life of cylinder-piston group of the ZMZ-40524.10 engine.
Multicriteria optimization in the study of active vehicle safety.
Authors: Markovnina A.I. , Makarov V.S. , Belyakov V.V. 
Published: December 2019

Abstract
Ensuring road safety is a paramount task to be solved by specialists in the field of automobile transport. It affects all aspects of the Driver-Car-Road-Environment system and is aimed at increasing the degree of protection of road users from traffic accidents, at reducing the degree of road traffic injuries and reducing the risk of mortality. Similar functions for ensuring road safety are performed by the active safety systems of the car, including intelligent driver assistance systems and assistants. With all the variety of possibilities of equipping automobiles with complex systems, there is a need to assess the feasibility and profitability of installing a particular complex of systems. For this, it is proposed to apply multi-criteria assessment methods. At the same time, the possibility of multi-parameter optimization according to two or more criteria is considered, respectively, several approaches to solving the problem are described. As a result, a concept is developed that is close to universal, in assessing the active safety systems of a car and intelligent systems.
Composition research of generator gas for application as motor fuel
Authors: Plotnikov S.A. , Biryukov A.L. , Zubakin A.S- 
Published: December 2019

Abstract
The problem of the lack of currently approved methodology for determining chemical composition of generator gas and the effect of gas composition when using it as a motor fuel on the operational and environmental performance of an internal combustion engine is discussed. A method for determining chemical composition of generator gas has been developed and tested, in which it is proposed to measure mass concentrations (volume fractions) of the determined components in the generator gas by the indicator (linear-colour) method. Experimental studies were carried out to determine chemical composition of the generator gas according to the developed technique. The studies were carried out on an experimental gas generator of original design, the novelty of which is confirmed by a patent for the invention. Charcoal and wood chocks were used as raw materials for production of generator gas. The composition of the generator gas in a parametric gas generator depends on the type of fuel (raw material), the temperature in the gasification zone, the number and spatial location of the injectors included in the operation and varies in the content of combustible components: H2 from 7% to 18%; CnHm - from 0.1% to 0.3%; CO - from 18% to 31%; CH4 - from 2% to 2.5%. The content of ballast in the generator gas also changes, so the O2 content is from 0.2% to 1.9%; N2 - from 48% to 57.3%; CO2 - from 3.2% to 10%. Experimental studies have confirmed the sufficient accuracy of the proposed methods.
Optimization of perlite steels mechanical properties for car fasteners stamping
Authors: Kuzmin A.N. , Filippov A.A. , Pachurin G.V. , Goncharova D.A. 
Published: December 2019

Abstract
The car fasteners made of pearlitic steels by cold stamping method are to meet special requirements for their structural and mechanical characteristics.
The hardware is made of hot-rolled steel, which cannot be used straight after the delivery for fasteners manufacturing due to the poor quality of the structure and surface layer. Therefore, calibrated rolled stock gets heat treatment before drawing. In addition, hardware of strength class 8.8 and higher obtained from alloy steels using cold heading machines are subjected to temper hardening, which often leads to surface decarburization, cracking and distortion of finished products, that afflicts labor and energy efficiency, and, thus, the final cost of production.
The article suggests a method for 35X and 38XA pearlitic steels stock treatment excluding recrystallization annealing, rod-like items temper hardening, and including isothermal operation to prevent decarburization, risks and distortion. Passing through the die, hardening the surface due to volume strain and thread rolling impart to M8 bolts and studs the mechanical properties corresponding to strength grades 8.8 and 9.8.
This study also has practical application, it allows manufacturers to determine the appropriate mode for producing automotive fasteners.
Accelerometer-Measured Physical Activity at Work and Need for Recovery: A Compositional Analysis of Cross-sectional Data
Authors: Stevens Matthew L , Crowley Patrick , Rasmussen Charlotte L , Hallman David M , Mortensen Ole S , Nygård Clas-Håkan , Holtermann Andreas 
Published: December 2019

AbstractObjectivesPrevious research has shown strong associations between occupational physical activity (OPA) and need for recovery (NFR). However this research has only utilized self-reported measures of OPA which may be biased. Thus, there is a need for investigating if the previously documented association between self-reported OPA and NFR can be found when using technical measures of OPA. There is also the need to investigate whether older workers are particularly susceptible to increased NFR, since age-related declines in physical capacity mean that it is likely these workers will have a higher NFR for a given physical activity. The aim of this study was to investigate the association between technically measured OPA and NFR, and whether this relationship is modified by age.MethodsThis study utilized data from the Danish Physical Activity Cohort with Objective Measurements cohort—comprising Danish workers (n = 840) from the cleaning, manufacturing, and transportation sectors. OPA was measured by accelerometers attached to the thigh and upper back for at least one work day and classified into four physical behaviour categories (sedentary, standing, light, or moderate/vigorous). NFR was measured using a shortened version of the Danish NFR scale. Analysis was conducted using linear regression and isotemporal substitution analyses for compositional data.ResultsThe overall association between OPA and NFR was statistically significant in the unadjusted model (P &lt; 0.001), but not when adjusted for age, sex, occupation, and shift work (P = 0.166). Isotemporal substitution showed small but significant reductions in NFR when increasing sedentary time relative to other behaviours (adjusted: ΔNFR = −0.010 [−0.019; −0.001]). There were no significant interactions between age and OPA (P = 0.409).ConclusionsThis study found significant associations between OPA and NFR, but the effect sizes were small. Reallocating 30 min to sedentary behaviours from other behaviours was associated with a reduced NFR, but the effect size may not be practically relevant. Moreover, no clear modifying effects of age were identified.
Predictive value of non-invasive right ventricle to pulmonary circulation coupling in systemic lupus erythematosus patients with pulmonary arterial hypertension
Authors: Guo Xiaoxiao , Lai Jinzhi , Wang Hui , Tian Zhuang , Wang Qian , Zhao Jiuliang , Li MengTao , Fang Quan , Fang Ligang , Liu Yongtai , Zeng Xiaofeng 
Published: December 2019

AbstractAimsPulmonary arterial hypertension (PAH) is a serious and devastating complication of systemic lupus erythematosus (SLE), especially when the right ventricle (RV) fails. Whether the ratio between tricuspid annular plane systolic excursion (TAPSE) and pulmonary artery systolic pressure (PASP) measured by echocardiography as a simple surrogate of RV to pulmonary circulation (PC) coupling predicts the outcome of SLE-associated PAH has not been investigated.Methods and resultsBetween February 2010 and August 2015, 112 consecutive patients with a diagnosis of SLE-associated PAH confirmed by right heart catheterization were enrolled prospectively. The endpoint was a composite of all-cause mortality and clinical worsening. Baseline clinical characteristics and echocardiographic assessment were analysed. Among all the patients, 47 (42%) patients experienced the endpoint (mean follow-up period 18.1 ± 12.0 months), including 20 patients who died during a median follow-up period of 48.5 months. Multivariable Cox regression analysis showed that TAPSE/PASP ratio [hazard ratio (HR) 0.004, P = 0.017] and 6-min walk distance (6MWD) (HR 0.997, P = 0.036) were the independent predictors for the endpoint. A three-group prediction risk was created based on combined assessment of the TAPSE/PASP ratio and 6MWD relative to their cut-off values. The patients with the worse RV-PC coupling (TAPSE/PASP &lt;0.184 mm/mmHg) and the lower 6MWD (&lt;395 m) had the highest risk (HR 4.62, confidence interval 2.27–9.41, P &lt; 0.001) of experiencing the endpoint.ConclusionThe TAPSE/PASP ratio, combined with 6MWD, provides clinical and prognostic insights into patients with SLE-associated PAH. A low TAPSE/PASP and low 6MWD identifies the subgroup of patients with high risk of poor prognosis.
Chromosome-scale assembly comparison of the Korean Reference Genome KOREF from PromethION and PacBio with Hi-C mapping information
Authors: Kim Hui-Su , Jeon Sungwon , Kim Changjae , Kim Yeon Kyung , Cho Yun Sung , Kim Jungeun , Blazyte Asta , Manica Andrea , Lee Semin , Bhak Jong 
Published: December 2019

Abstract

Background
Long DNA reads produced by single-molecule and pore-based sequencers are more suitable for assembly and structural variation discovery than short-read DNA fragments. For de novo assembly, Pacific Biosciences (PacBio) and Oxford Nanopore Technologies (ONT) are the favorite options. However, PacBio's SMRT sequencing is expensive for a full human genome assembly and costs more than $40,000 US for 30× coverage as of 2019. ONT PromethION sequencing, on the other hand, is 1/12 the price of PacBio for the same coverage. This study aimed to compare the cost-effectiveness of ONT PromethION and PacBio's SMRT sequencing in relation to the quality.

Findings
We performed whole-genome de novo assemblies and comparison to construct an improved version of KOREF, the Korean reference genome, using sequencing data produced by PromethION and PacBio. With PromethION, an assembly using sequenced reads with 64× coverage (193 Gb, 3 flowcell sequencing) resulted in 3,725 contigs with N50s of 16.7 Mb and a total genome length of 2.8 Gb. It was comparable to a KOREF assembly constructed using PacBio at 62× coverage (188 Gb, 2,695 contigs, and N50s of 17.9 Mb). When we applied Hi-C–derived long-range mapping data, an even higher quality assembly for the 64× coverage was achieved, resulting in 3,179 scaffolds with an N50 of 56.4 Mb.

Conclusion
The pore-based PromethION approach provided a high-quality chromosome-scale human genome assembly at a low cost with long maximum contig and scaffold lengths and was more cost-effective than PacBio at comparable quality measurements.
On the use of the coda of seismic noise autocorrelations to compute H/V spectral ratios
Authors: Tchawe F N , Froment B , Campillo M , Margerin L 
Published: December 2019

SUMMARYThe horizontal to vertical spectral ratio (HVSR) of seismic ambient noise has been proven to be a fast and efficient method for characterizing the 1-D resonance frequency of the local subsurface in a practical framework. Over the last decades, theories have been developed in order to extend the exploitation of HVSR beside the frequency of its first peak, notably the diffuse field assumption (DFA) which links the HVSR to the Green’s function of the local medium assuming the diffuseness of the seismic ambient noise wavefield. However, the underlying assumption of the seismic ambient noise being a diffuse, equipartitioned field may not be satisfied under certain circumstances. In order to exploit the contribution of scattering in forging diffuse wave fields, we leverage the advantages of coda waves and present a novel procedure for computing the HVSR, using the coda part of ambient noise correlations. We applied this technique to data gathered at the plio-quaternary sedimentary basin of Argostoli, Greece. Results on this data set show the potential of the method to improve the temporal stability of the HVSR measurements compared to the classical computation, and the fit with the theoretical HVSR curve derived from the DFA theory. These results suggest that this procedure could help in extracting physical information from the HVSR and thus could lead to an extended use of these measurements to characterize the mechanical properties of the medium.
What can P-wave polarization direction data tell us about subsurface velocity structures?
Authors: Jing Xili , Li Li 
Published: December 2019

SUMMARY
As seismic waves propagate in the Earth, the directions of particle motions are affected by the media that they encounter, and thus seismic wave polarization direction carries the information on the media. So far there remains unclear about what can be inferred from the P-wave polarization direction data. For clarifying it, we discuss the mapping relation between polarization direction and velocity distribution. It is found that the velocity model cannot be derived uniquely from the polarization direction data. By analysing the relation between slowness vectors of the seismic ray at the source and the receiver, we find that relative velocity gradient is the physical quantity that describes the capability to deflect seismic rays in a continuous medium. The equation describing the relation between polarization direction and relative velocity gradient is given. For imaging relative velocity gradients, we derive the calculation formula for the partial derivative of polarization direction with respect to velocity gradient parameters. Synthetic experiments are conducted. The test results demonstrate that the absolute velocity model cannot be recovered from P-wave polarization direction data, but the relative velocity gradient model can. Polarization direction tomography gives a way to build gradient maps for the geometric characteristic of the subsurface velocity structures.
3-D shear wave velocity model of the lithosphere below the Sardinia–Corsica continental block based on Rayleigh-wave phase velocities
Authors: Magrini Fabrizio , Diaferia Giovanni , Fadel Islam , Cammarano Fabio , van der Meijde Mark , Boschi Lapo 
Published: December 2019

SUMMARY
Rayleigh-wave dispersion curves from both ambient noise and teleseismic events allow us to provide the first high-resolution 3-D shear wave velocity (VS) model of the crust and upper mantle below the Sardinia–Corsica microplate, an important continental block for understanding the evolution of the central-western Mediterranean. For a wide range of periods (from 3 to ∼30 s), the phase velocities of the study area are systematically higher than those measured within the Italian peninsula, in agreement with a colder geotherm. Relative and absolute variations in the VS allow us to detect a very heterogeneous upper crust down to 8 km, as opposed to a relatively homogeneous middle and lower crust. The isosurface at 4.1 km s−1 is consistent with a rather flat Moho at a depth of 28.0 ± 1.8 km (2σ). The lithospheric mantle is relatively cold, and we constrain the thermal lithosphere–asthenosphere boundary at ∼100 km. We find our estimate consistent with a continental geotherm based on a surface heat flow of 60 mW m−2. Our results suggest that most of the lithosphere endured the complex history of deformation experienced by the study area and imply, in general, that deep tectonic processes do not easily destabilize the deeper portion of the continental lithosphere, despite leaving a clear surface signature.
A solid/fluid substitution scheme constrained by pore-scale numerical simulations
Authors: Sun Yongyang , Gurevich Boris , Glubokovskikh Stanislav , Lebedev Maxim , Squelch Andrew , Arns Christoph , Guo Junxin 
Published: December 2019

SUMMARYEstimating the effects of pore filling material on the elastic moduli or velocities of porous and fractured rocks attracts widespread attention. This effect can be modelled by a recently proposed triple-porosity scheme, which quantifies this effect from parameters of the pressure dependency of the elastic properties of the dry rock. This scheme divides total porosity into three parts: compliant, intermediate and stiff. Each type of pores is assumed to be spheroidal and characterized by a single aspect ratio. However, the implementation of this model requires the asymptotic values of the elastic moduli at much higher pressures where only non-closable pores remain open. Those pressures are beyond the capacity of most rock physics laboratories and can even crush typical sandstone samples. Experimental data at such pressures are usually unavailable. To address this issue, we introduce pore-scale numerical simulations in conjunction with effective medium theories (EMT) to compute the asymptotic values directly from the microtomographic images. This workflow reduces the uncertainty of model predictions on the geometric information of stiff pores and strengthens the predictive power and usefulness of the model without any adjustable parameters. Applying this to a Bentheim sandstone fully filled with liquid and solid octadecane gives a reasonable match between model predictions and laboratory measurements. This success verifies the accuracy and applicability of the model and indicates its potential in further exploitation and characterization of heavy oil reservoirs and other similar reservoirs.
Reclaiming Children after the Armenian Genocide: Neutral House in Istanbul
Authors: Gzoyan Edita , Galustyan Regina , Khachatryan Shushan 
Published: December 2019

Abstract
During the Armenian Genocide the Turkish Government forcibly converted and assimilated Armenian children. The defeat of the Ottoman Empire in WWI brought the opportunity to retrieve such children, whose identities and future became a battleground between Armenians and Turks. This article addresses the fate of these child-survivors, many of whom, after being rescued, continued to deny their Armenian identities. The article presents a history of Neutral House, a unique organization established in Istanbul to return these children to their nation.
Optimizing image-based protocol to monitor macroepibenthic communities colonizing artificial structures
Authors: Taormina Bastien , Marzloff Martin P , Desroy Nicolas , Caisey Xavier , Dugornay Olivier , Metral Thiesse Emmanuelle , Tancray Aurélien , Carlier Antoine 
Published: December 2019

Abstract
Underwater imagery is increasingly used as an effective and repeatable method to monitor benthic ecosystems. Nevertheless, extracting ecologically relevant information from a large amount of raw images remains a time-consuming and somewhat laborious challenge. Thus, underwater imagery processing needs to strike a compromise between time-efficient image annotation and accuracy in quantifying benthic community composition. Designing and implementing robust image sampling and image annotation protocols are therefore critical to rationally address these trade-offs between ecological accuracy and processing time. The aim of this study was to develop and to optimize a reliable image scoring strategy based on the point count method using imagery data acquired on tide-swept macroepibenthic communities. Using a stepwise approach, we define an underwater imagery processing protocol that is effective in terms of (i) time allocated to overall image, (ii) reaching a satisfactory accuracy to estimate the occurrence of dominant benthic taxa, and (iii) adopting a sufficient taxonomic resolution to describe changes in community composition. We believe that our method is well adapted to investigate the composition of epibenthic communities on artificial reefs and can be useful in surveying colonization of other human structures (wind turbine foundations, pipelines, etc.) in coastal areas. Our strategy meets the increasing demand for inexpensive and time-effective tools for monitoring changes in benthic communities in a context of increasing coastal artificialization pressures.