bluuebunny/crossref_metadata_2025 huggingface dataset:
The geometry of the magnetic field in the central molecular zone measured by PILOT
Authors: Mangilli A. , Aumont J. , Bernard J.-Ph. , Buzzelli A. , de Gasperis G. , Durrive J. B. , Ferriere K. , Foënard G. , Hughes A. , Lacourt A. , Misawa R. , Montier L. , Mot B. , Ristorcelli I. , Roussel H. , Ade P. , Alina D. , de Bernardis P. , de Gouveia Dal Pino E. , Dubois J. P. , Engel C. , Guillet V. , Hargrave P. , Laureijs R. , Longval Y. , Maffei B. , Magalhes A. M. , Marty C. , Masi S. , Montel J. , Pajot F. , Pérot E. , Rodriguez L. , Salatino M. , Saccoccio M. , Savini G. , Stever S. , Tauber J. , Tibbs C. , Tucker C.
Published: August 2019

We present the first far infrared (FIR) dust emission polarization map covering the full extent of Milky Way’s central molecular zone (CMZ). The data, obtained with the PILOT balloon-borne experiment, covers the Galactic center region − 2° < ℓ < 2°, − 4° < b < 3° at a wavelength of 240 μm and an angular resolution of 2.2′. From our measured dust polarization angles, we infer a magnetic field orientation projected onto the plane of the sky (POS) that is remarkably ordered over the full extent of the CMZ, with an average tilt angle of ≃22° clockwise with respect to the Galactic plane. Our results confirm previous claims that the field traced by dust polarized emission is oriented nearly orthogonally to the field traced by GHz radio synchrotron emission in the Galactic center region. The observed field structure is globally compatible with the latest Planck polarization data at 353 and 217 GHz. Upon subtraction of the extended emission in our data, the mean field orientation that we obtain shows good agreement with the mean field orientation measured at higher angular resolution by the JCMT within the 20 and 50 km s−1 molecular clouds. We find no evidence that the magnetic field orientation is related to the 100 pc twisted ring structure within the CMZ. The low polarization fraction in the Galactic center region measured with Planck at 353 GHz combined with a highly ordered projected field orientation is unusual. This feature actually extends to the whole inner Galactic plane. We propose that it could be caused by the increased number of turbulent cells for the long lines of sight towards the inner Galactic plane or to dust properties specific to the inner regions of the Galaxy. Assuming equipartition between magnetic pressure and ram pressure, we obtain magnetic field strength estimates of the order of 1 mG for several CMZ molecular clouds.
Iron abundance distribution in the hot gas of merging galaxy clusters
Authors: Urdampilleta I. , Mernier F. , Kaastra J. S. , Simionescu A. , de Plaa J. , Kara S. , Ercan E. N.
Published: August 2019

We presentXMM-Newton/EPIC observations of six merging galaxy clusters and study the distributions of their temperature, iron (Fe) abundance and pseudo-entropy along the merging axis. For the first time, we focused simultaneously, and in a comprehensive way, on the chemical and thermodynamic properties of the newly collided intra cluster medium (ICM). The Fe distribution of these clusters along the merging axis is found to be in good agreement with the azimuthally-averaged Fe abundance profile in typical non-cool-core clusters out tor500. In addition to showing a moderate central abundance peak, though less pronounced than in relaxed systems, the Fe abundance flattens at large radii towards ∼0.2−0.3Z⊙. Although this shallow metal distribution is in line with the idea that disturbed, non-cool-core clusters originate from the merging of relaxed, cool-core clusters, we find that in some cases, remnants of metal-rich and low entropy cool cores can persist after major mergers. While we obtain a mild anti-correlation between the Fe abundance and the pseudo-entropy in the (lower entropy,K= 200−500 keV cm2) inner regions, no clear correlation is found at (higher entropy,K= 500−2300 keV cm2) outer radii. The apparent spatial abundance uniformity that we find at large radii is difficult to explain through an efficient mixing of freshly injected metals, particularly in systems for which the time since the merger is short. Instead, our results provide important additional evidence in favour of the early enrichment scenario in which the bulk of the metals are released outside galaxies atz >  2−3, and extend it from cool-core and (moderate) non-cool-core clusters to a few of the most disturbed merging clusters as well. These results constitute a first step toward a deeper understanding of the chemical history of merging clusters.
The Hubble constant determined through an inverse distance ladder including quasar time delays and Type Ia supernovae
Authors: Taubenberger S. , Suyu S. H. , Komatsu E. , Jee I. , Birrer S. , Bonvin V. , Courbin F. , Rusu C. E. , Shajib A. J. , Wong K. C.
Published: August 2019

Context.The precise determination of the present-day expansion rate of the Universe, expressed through the Hubble constantH0, is one of the most pressing challenges in modern cosmology. Assuming flat ΛCDM,H0inference at high redshift using cosmic microwave background data fromPlanckdisagrees at the 4.4σlevel with measurements based on the local distance ladder made up of parallaxes, Cepheids, and Type Ia supernovae (SNe Ia), often referred to as Hubble tension. Independent cosmological-model-insensitive ways to inferH0are of critical importance.

Aims.We apply an inverse distance ladder approach, combining strong-lensing time-delay distance measurements with SN Ia data. By themselves, SNe Ia are merely good indicators of relative distance, but by anchoring them to strong gravitational lenses we can obtain anH0measurement that is relatively insensitive to other cosmological parameters.

Methods.A cosmological parameter estimate was performed for different cosmological background models, both for strong-lensing data alone and for the combined lensing + SNe Ia data sets.

Results.The cosmological-model dependence of strong-lensingH0measurements is significantly mitigated through the inverse distance ladder. In combination with SN Ia data, the inferredH0consistently lies around 73–74 km s−1Mpc−1, regardless of the assumed cosmological background model. Our results agree closely with those from the local distance ladder, but there is a > 2σtension withPlanckresults, and a ∼1.5σdiscrepancy with results from an inverse distance ladder includingPlanck, baryon acoustic oscillations, and SNe Ia. Future strong-lensing distance measurements will reduce the uncertainties inH0from our inverse distance ladder.
Electron counting statistics for non-additive environments
Authors: McConnell Conor , Nazir Ahsan
Published: August 2019

Molecular electronics is a rapidly developing field focused on using molecules as the structural basis for electronic components. It is common in such devices for the system of interest to couple simultaneously to multiple environments. Here, we consider a model comprising a double quantum dot (or molecule) coupled strongly to vibrations and weakly to two electronic leads held at arbitrary bias voltage. The strong vibrational coupling invalidates treating the bosonic and electronic environments simply as acting additively, as would be the case in the weak coupling regime or for flat leads at infinite bias. Instead, making use of the reaction coordinate framework, we incorporate the dominant vibrational coupling effects within an enlarged system Hamiltonian. This allows us to derive a nonadditive form for the lead couplings that accounts properly for the influence of strong and non-Markovian coupling between the double dot system and the vibrations. Applying counting statistics techniques, we track electron flow between the double dot and the electronic leads, revealing both strong-coupling and nonadditive effects in the electron current, noise, and Fano factor.
Low-energy proton calibration and energy-dependence linearization of EBT-XD radiochromic films
Authors: Vallières S. , Bienvenue C. , Puyuelo-Valdes P. , Salvadori M. , d’Humières E. , Schiettekatte F. , Antici P.
Published: August 2019

In this work, we calibrate the newly developed EBT-XD radiochromic films (RCFs) manufactured by Gafchromictm using protons in the energy range of 4–10 MeV. Irradiation was performed on the 2 × 6 MV tandem linear accelerator located at the Université de Montréal. The RCFs were digitized using an Epson Perfection V700 flatbed scanner using both the red-green-blue and grayscale channels. The proton fluences were measured with Faraday cups calibrated in absolute terms. The linear energy transfer function within the active layer of the films was calculated using the mass stopping power tables coming from the PSTAR database from the National Institute of Standards and Technology (NIST) to allow retrieval of the deposited dose. We find that the calibration curves for 7 and 10 MeV protons are nearly equivalent. The 4 MeV calibration curves exhibit a quenching effect due to the Bragg peak that falls close to the active layer. A linearization of this energy dependence was developed using a semiempirical parametric model to allow the generation of calibration curves for any incident proton energy within the present range. Excellent correspondence (<5% dose difference for the same netOD) of the 10 MeV calibration curves was noted when compared to existing high-energy proton (148.2 MeV) calibration curves reported in the literature. Our calibration extends the range of operation of EBT-XD films to low-energy proton beam dosimetry.
Vibrational coherence transfer illuminates dark modes in models of the FeFe hydrogenase active site
Authors: Eckert Peter A. , Kubarych Kevin J.
Published: August 2019

Within the conceptual framework of Redfield theory, the optical response function arises from the dynamical evolution of the system’s density operator, where nonunitary relaxation is encoded in the Redfield relaxation superoperator. In the conventional approach, the so-called secular approximation neglects terms that induce transitions between distinct coherences and among coherences and populations. The rationale is that these nonsecular terms are small in comparison to the far more dominant population relaxation and coherence dephasing contributions. Since two-dimensional infrared (2D-IR) spectroscopy has significant contributions arising from population relaxation and transfer pathways, it can be challenging to isolate signatures of the nonsecular relaxation. We report here that in three diiron dithiolate hexacarbonyl complexes that serve as small-molecule models of the [FeFe] hydrogenase H-cluster subsite, a fortuitous vibrational energy structure enables direct and clear signatures of vibrational coherence transfer in alkane solution. This finding holds promise towards developing a molecularly detailed understanding of the mechanism of vibrational coherence transfer processes, thanks to the ease of synthesizing derivatives based on the chemical modularity of these well studied diiron compounds. In addition to the fundamental need to characterize coherence transfer in molecular spectroscopy, we find in this set of molecules a practical utility for the nonsecular dynamics: the ability to determine the frequency of an IR-inactive mode. A coherence generated during the waiting time of the 2D-IR measurement transfers to a coherence involving the single dark CO stretching mode, which modulates some peak amplitudes in the 2D spectrum, revealing its transient excitation.
Phylogenetic relationships and biogeographic history of the Australian trapdoor spider genus Conothele (Araneae: Mygalomorphae: Halonoproctidae): diversification into arid habitats in an otherwise tropical radiation
Authors: Huey Joel A. , Hillyer Mia J. , Harvey Mark S.
Published: August 2019

In Australia, climate change and continental drift have given rise to a complex biota comprising mesic specialists, arid-adapted lineages, and taxa that have arrived on the continent from Asia. We explore the phylogenetic diversity and biogeographic history of the Australian trapdoor spider genus Conothele Thorell, 1878 that is widespread in Australia’s monsoonal tropics and arid zone. We sequenced three mtDNA and five nuDNA markers from 224 specimens. We reconstructed the phylogenetic relationships among specimens and estimated the number of operational taxonomic units (OTUs) using species delimitation methods. The timing of divergences was estimated and ancestral area reconstructions were conducted. We recovered 61 OTUs, grouped into four major clades; a single clade represented by an arboreal ecomorph, and three fossorial clades. The Australian Conothele had a crown age of ~19 million years, and ancestral area reconstructions showed a complex history with multiple transitions among the monsoonal tropics, central arid zone, south-west and Pilbara bioregion. Conothele arrived on the continent during periods of biotic exchange with Asia. Since then, Conothele has colonised much of the Australian arid and monsoonal zones, during a period of climatic instability. The Pilbara bioregion harbours high lineage diversity, emphasising the role of climate refugia.
Direct observation of 2-dimensional ices on different surfaces near room temperature without confinement
Authors: Zhu Chongqin , Gao Yurui , Zhu Weiduo , Jiang Jian , Liu Jie , Wang Jianjun , Francisco Joseph S. , Zeng Xiao Cheng
Published: August 2019

Significance

Many metal surfaces can stabilize 2-dimensional (2D) water monolayers or various structures of 2D ices, depending on the temperature and metal surface structures. Understanding of 2D ice formation on different surfaces at the molecular level, however, remains incomplete. We report simulation evidence of 2D ice formation on various surfaces without confinement and dependence of the 2D structure of water on the hydrophobicity and structure of underlying surface. The direct transformation of water nanodroplets to different 2D ices is shown, either on a smooth model surface or on fcc-crystal surfaces near room temperature. Physical mechanism related to the formation of different 2D ices is elucidated, which offers deeper insight into how the 2D ice formation is related to the water–surface interactions.
Two distinct sources – one target
Authors: Diewald Gabriele , Stathi Katerina
Published: August 2019

Cross-linguistic diachronic studies have focused on the parallel or divergent development of cognate or functionally equivalent items. This paper traces the diachronic convergent development of two unrelated items by means of a case study, the development of the German verbscheinen‘shine, emit light’ and Englishseem‘(originally) befit, beseem’. Despite their different source meanings, the two verbs have grammaticalized into evidential markers, as is evidenced by the constructionsscheinen+zu+ infinitive andseem+to+ infinitive. We use historical corpus data to show that the two verbs have converged both semantically and syntactically. Semantically the verbs converge when they acquire the sense ‘appear, become visible’, a well-known source of evidentials. Syntactically,scheinenandseemcome to occur in the same range of constructional patterns. This development is more advanced in English, so that it is ahead of German by at least four centuries.
Interface structure between magnesium matrix and SiCp
Authors: Shen M. J. , Jia J. H. , Ying T.
Published: August 2019

The microstructure of magnesium matrix composite (MMC) was investigated by transmission electron microscopy, and fracture behaviour of composite by step-by-step tensile in the strain range of 0.8–2.0% has been determined using the dislocation and microcrack analysis. The results indicated that the interface between matrix and double-sized SiC particle (SiCp) showed a good combination. With increasing the strain from 0 to 2.0%, the dislocation density was gradually increased, especially in the interface of SiCp/matrix. Some microcracks can be found in the interface between micrometre-SiCp and matrix while no microcracks were observed around nano-SiCp.
A Monte Carlo based radiation response modelling framework to assess variability of clinical RBE in proton therapy
Authors: Eulitz J , Lutz B , Wohlfahrt P , Dutz A , Enghardt W , Karpowitz C , Krause M , Troost E G C , Lühr A
Published: August 2019

The clinical implementation of a variable relative biological effectiveness (RBE) in proton therapy is currently controversially discussed. Initial clinical evidence indicates a variable proton RBE, which needs to be verified. In this study, a radiation response modelling framework for assessing clinical RBE variability is established. It was applied to four selected glioma patients (grade III) treated with adjuvant radio(chemo)therapy and who developed late morphological image changes on T1-weighted contrast-enhanced (T1w-CE) magnetic resonance (MR) images within approximately two years of recurrence-free follow-up. The image changes were correlated voxelwise with dose and linear energy transfer (LET) values using univariable and multivariable logistic regression analysis. The regression models were evaluated by the area-under-the-curve (AUC) method performing a leave-one-out cross validation. The tolerance dose TD50 at which 50% of patient voxels experienced toxicity was interpolated from the models. A Monte Carlo (MC) model was developed to simulate dose and LET distributions, which includes variance reduction (VR) techniques to decrease computation time. Its reliability and accuracy were evaluated based on dose calculations of the clinical treatment planning system (TPS) as well as absolute dose measurements performed in the patient specific quality assurance.

Morphological image changes were related to a combination of dose and LET. The multivariable models revealed cross-validated AUC values of up to 0.88. The interpolated TD50 curves decreased with increasing LET indicating an increase in biological effectiveness. The MC model reliably predicted average TPS dose within the clinical target volume as well as absolute water phantom dose measurements within 2% accuracy using dedicated VR settings.

The observed correlation of dose and LET with late brain tissue damage suggests considering RBE variability for predicting chronic radiation-induced brain toxicities. The MC model simulates radiation fields in patients precisely and time-efficiently. Hence, this study encourages and enables in-depth patient evaluation to assess the variability of clinical proton RBE.
Dipole–dipole interactions enhance non-Markovianity and protect information against dissipation*
Authors: Jan Munsif , Xu Xiao-Ye , Wang Qin-Qin , Chen Zhe , Han Yong-Jian , Li Chuan-Feng , Guo Guang-Can
Published: August 2019

Preserving non-Markovianity and quantum entanglement from decoherence effect is of theoretical and practical significance in the quantum information processing technologies. In this context, we study a system S that is initially correlated with an ancilla A, which interacts with the environment E via an amplitude damping channel. We also consider dipole-dipole interactions (DDIs) between the system and ancilla, which are responsible for strong correlations. We investigate the impact of DDIs and detuning on the non-Markovianity and information exchange in different environments. We show that DDIs are not only better than detuning at protecting the information (without destroying the memory effect) but also induce memory by causing a transition from Markovian to non-Markovian dynamics. In contrast, although detuning also protects the information, it causes a transition from non-Markovian to the Markovian dynamics. In addition, we demonstrate that the non-Markovianity grows with increasing DDI strength and diminishes with increasing detuning. We also show that the effects of negative detuning and DDIs can cancel out each other, causing a certain loss of coherence and information.
First polar direct-drive exploding-pusher target experiments on the ShenGuang laser facility*
Authors: Yu Bo , Yang Jiamin , Huang Tianxuan , Wang Peng , Shang Wanli , Qiao Xiumei , Deng Xuewei , Zhang Zhanwen , Song Zifeng , Tang Qi , Peng Xiaoshi , Chen Jiabin , Li Yulong , Jiang Wei , Pu Yudong , Yan Ji , Chen Zhongjing , Dong Yunsong , Zheng Wudi , Wang Feng , Jiang Shaoen , Ding Yongkun , Zheng Jian
Published: August 2019

Low density and low convergence implosion occurs in the exploding-pusher target experiment, and generates neutrons isotropically to develop a high yield platform. In order to validate the performance of ShenGuang (SG) laser facility and test nuclear diagnostics, all 48-beam lasers with an on-target energy of 48 kJ were firstly used to drive room-temperature, DT gas-filled glass targets. The optimization has been carried out and optimal drive uniformity was obtained by the combination of beam repointing and target. The final irradiation uniformity of less than 5% on polar direct-drive capsules of

540

μ
m

in diameter was achieved, and the highest thermonuclear yield of the polar direct-drive DT fuel implosion at the SG was 1.04×1013. The experiment results show neutron yields severely depend on the irradiation uniformity and laser timing, and decrease with the increase of the diameter and fuel pressure of the target. The thin CH ablator does not impact the implosion performance, but the laser drive uniformity is important. The simulated results validate that the

cos
γ

distribution laser design is reasonable and can achieve a symmetric pressure distribution. Further optimization will focus on measuring the symmetry of the hot spot by self-emission imaging, increasing the diameter, and decreasing the fuel pressure.
Dynamical anisotropic magnetoelectric effects at ferroelectric/ferromagnetic insulator interfaces*
Authors: Li Yaojin , Koval Vladimir , Jia Chenglong
Published: August 2019

The interfacial magnetoelectric interaction originating from multi-orbital hopping processes with ferroelectric-associated vector potential is theoretically investigated for complex-oxide composite structures. Large mismatch in the electrical permittivity of the ferroelectric and ferromagnetic materials gives rise to giant anisotropic magnetoelectric effects at their interface. Our study reveals a strong linear dynamic magnetoelectric coupling which genuinely results in electric control of magnetic susceptibility. The constitutive conditions for negative refractive index of multiferroic composites are determined by the analysis of light propagation.
Structural transitions in NaNH2 via recrystallization under high pressure*
Authors: Huang Yanping , Haung Xiaoli , Wang Xin , Zhang Wenting , Zhou Di , Zhou Qiang , Liu Bingbing , Cui Tian
Published: August 2019

Multiple phase transitions are detected in sodium amide (NaNH2), an important hydrogen storage material, upon compression in diamond anvil cells (DAC) by using Raman spectroscopy and x-ray diffraction (XRD) measurements. Additional Bragg reflections appear on lower and higher angle sides of the original ones at ∼ 1.07 GPa and 1.84 GPa, accompanied by obvious changes in Raman spectroscopy, respectively. It reveals that NaNH2 undergoes the high-pressure phase sequence (α–β–γ) up to 20 GPa at room temperature. Spectral analysis indicates an orthorhombic structure with PBAN space group for the γ phase. We also experimentally observe high pressure induced recrystallization in alkaline amide compounds for the first time.
Simulations and measurements of friction in oscillating flow
Authors: Hamran K A
Published: August 2019

Rapid changes in the operating point of a hydropower plant cause transients in the hydraulic system. The flow will oscillate between the surge shaft and the reservoir until the oscillations are damped out by the friction. This paper investigates different friction models for oscillating flow, such as a quasi-steady model, Vítkovský’s model, and a one-term model. The governing equations for transient flow were solved by using rigid water column theory. The simulations were compared with experimental results from a small-scale test rig. The test rig consisted of a small reservoir, a horizontal pipe, and a surge shaft. The oscillations were induced by closing a valve downstream of the surge shaft. Measurements were obtained with pressure transducers.
Numerical study of sediment erosion in guide vanes of a high head Francis turbine
Authors: Acharya N. , Trivedi C. , Wahl N. M. , Gautam S. , Chitrakar S. , Dahlhaug O. G.
Published: August 2019

Erosion in guide vanes (GVs) has been reported from several power plants in Himalayan and Andes basins which affects the efficiency of turbine. Wear in clearance gaps (CGs) increases with the sediments passing through them resulting in increased gap size, which disturbs the flow into the runner inducing more losses. This paper investigates the flow and erosion pattern around GVs along with the leakage flow. Simulations are carried out in full GV and runner model with varying CGs with the inclusion of sediment. 3 types of clearance gaps viz., 0.5 mm, 1 mm and 1.5 mm are included and numerical results obtained are compared with the photograph of the erosion affected guide vanes. Result shows that erosion was prevalent in regions downstream of the mid-chord position inside the CG due to high pressure difference between two sides of GVs and the leakage flow induced from the pressure difference mixes with the main flow forming a vortex filament, which is driven towards the runner inlet.
Assessment and Numerical Analysis of Hydropower Tunnel in Lesser Himalayan Region of Nepal- A Case Study
Authors: Sundar Khadka Shyam , Karki Sujan , Chhushyabaga Bimal , Kumar Maskey Ramesh
Published: August 2019

This paper is focused on the assessment and numerical analysis of hydropower tunnel of the Lesser Himalayan Region of Nepal. This region lies between two major faults namely Main Boundary Thrust (MBT) and the Main Central Thrust (MCT) with weak rock mass like phyllite, schist, gneiss, phyllitic schist, etc. Thus, to overcome the stability problems during underground construction, proper rock support system must be installed. Rock mass classification systems are commonly used for estimating the rock support system in this region, but this approach is inadequate to address the underground stability problems. In this study, numerical analysis is done to define the requirement of support and the result compared to actual support provided in selected case study. Analytical approach is used along with two-dimensional Finite Element Analysis using the software, RS2 provided by RocScience for the study. Finally, required modification of the provided support has been suggested to overcome the problem faced in the selected tunnel.
Development of an information model of a virtual space of a historically significant territory
Authors: Gorelov I , Nemtinov V , Nemtinova Y
Published: August 2019

The article examines the questions of creating a virtual space of a historically significant territory as a means of communication and effective civil and patriotic education of young people. The proposed formal description of the model of the virtual space includes the sum of knowledge about a historically significant area (a historical site) presented in the form of a graph structure of frames. The creation of a virtual space in the form of a virtual museum is carried out using an open source software platform OpenSimulator 0.9.0, which is a server platform for 3D virtual worlds. Visualization of the museum is available to all Internet users. Thus, a thematic information environment has been created to provide access to relevant information and contributes to the growth of youth interest in the problems of national culture, history, and civil culture. In addition, an important role is played by the social aspect, as within the virtual world users can interact with others, observe their movements and actions, and communicate with them in real time.
Digital transformation of learning processes and the development of competencies in the virtual machine-building enterprise environment
Authors: Pozdneev B , Tolok A , Ovchinnikov P , Kupriyanenko I , Levchenko A , Sharovatov V
Published: August 2019

The paper presents the results of the pilot project “Virtual Machine-Building Enterprise”. It was developed for multi-level learning to meet the needs of the national digital economy and the digital industry. The profile of requirements for end-to-end learning (baccalaureate - magistracy - postgraduate) of prospective personnel in the digital development of machine-building enterprises has been substantiated. E-Portfolio model has been developed in accordance with the requirements of the standards GOST R 57720-2017 and ISO/IEC TR 20013:2015 to manage the digital competency development in the learning process and practical activities. The pilot project “Virtual Machine-Building Enterprise” was implemented at the initiative of MSUT “STANKIN”. It is a corporate technological platform for the digital machine-building development with the participation of industry, IT sector and technical universities. The architecture and functional model of a virtual enterprise are developed taking into account the principles of Industry 4.0, fundamental standards in automation systems integration (ERP, MES, CRM, CAD, CAE, CAPP, PLM, etc.) and e-learning (LMS, CMS, etc.). The educational programs are developed in accordance with the requirements of the FSES 3++, Professional Standards and qualification requirements for Chief Digital Officer. In the future, the pilot project “Virtual Machine-Building Enterprise” should be the basis for the formation of a digital technological university model.
Development of an online application for determination of thermo-physical properties of substances
Authors: Egorov S , Nemtinov V , Nemtinova Y , Egorov E
Published: August 2019

The article deals with development of a web application for determining thermo-physical properties of substances. A distinctive feature of the application is in using the method of forming functional dependencies in order to determine thermodynamic properties of a working medium for the regions of their liquid, steam, and gas phases that have first-order discontinuities at the inter-phase boundaries. The software package for mathematical modeling of thermodynamic processes, which includes a web application, is considered. Reference systems and computing services for performing mathematical calculations online are described. Examples of procedures used in the application to determine the properties of substances on the experimental data tables are given. The areas of using the application are identified.
Composite version of B&B algorithm: experimental verification of the efficiency
Authors: Groppen V O , Berko A A
Published: August 2019

The aim of this paper is to verify the efficiency for a composite version of branch and bound algorithm combining B&B branching strategy and bounds computing with the pruning rules used in dynamic programming for selecting of direction of movement by a search tree. As criteria of efficiency we used random access memory (RAM) and time gains of finding integer programming problem solution by a composite version of branch and bound algorithm in comparison with its traditional implementation. The number of variables in the problems and restrictions did not exceed 25 and 15, respectively. Experimental verification have shown that for solving time used as a criterion of the efficiency, the advantages of composite version are beyond doubt compared to the used RAM value as criterion often taking the side of the classical B&B algorithm.
Mathematical modeling of the synthesis process of vinyl acetate
Authors: Arapov D , Tikhomirov S , Podvalny S , Denisenko V , Avcinov I
Published: August 2019

A complete mathematical modeling of the technological process of manufacturing vinyl acetate monomer by vapor-phase method has been implemented. The model is partial differential equations of the material and energy balance and catalyst aging. An algorithm for an integrated equation based on the second-order Gregg-Bulirsh-Shter rectangle symbol has been developed. The error in modeling the process is equal (CH3COOCH=CH2) ± 5.4% rel. for the target matter, and (CO2) ± 6.4% rel. for the secondary substance The kinetic coefficients of differential equations, namely the pre-exponential factors and the activation energy have been refined. The obtained data of the modeling of the vapor-phase manufacturing process of vinyl acetate are shown in the form of tables and graphic three-dimensional dependencies of quality indicators on technological parameters.
Significant feedbacks of wetland methane release on climate change and the causes of their uncertainty
Authors: Gedney N , Huntingford C , Comyn-Platt E , Wiltshire A
Published: August 2019

Emissions from wetlands are the single largest source of the atmospheric greenhouse gas (GHG) methane (CH4). This may increase in a warming climate, leading to a positive feedback on climate change. For the first time, we extend interactive wetland CH4 emissions schemes to include the recently quantified, significant process of CH4 transfer through tropical trees. We constrain the parameterisations using a multi-site flux study, and biogeochemical and inversion models. This provides an estimate and uncertainty range in contemporary, large-scale wetland emissions and their response to temperature. To assess the potential for future wetland CH4 emissions to feedback on climate, the schemes are forced with simulated climate change using a ‘pattern-scaling’ system, which links altered atmospheric radiative forcing to meteorology changes. We perform multiple simulations emulating 34 Earth System Models over different anthropogenic GHG emissions scenarios (RCPs). We provide a detailed assessment of the causes of uncertainty in predicting wetland CH4–climate feedback. Despite the constraints applied, uncertainty from wetland CH4 emission modelling is greater that from projected climate spread (under a given RCP). Limited knowledge of contemporary global wetland emissions restricts model calibration, producing the largest individual cause of wetland parameterisation uncertainty. Wetland feedback causes an additional temperature increase between 0.6% and 5.5% over the 21st century, with a feedback on climate ranging from 0.01 to 0.11 Wm−2 K−1. Wetland CH4 emissions amplify atmospheric CH4 increases by up to a further possible 25.4% in one simulation, and reduce remaining allowed anthropogenic emissions to maintain the RCP2.6 temperature threshold by 8.0% on average.
Are e-scooters polluters? The environmental impacts of shared dockless electric scooters
Authors: Hollingsworth Joseph , Copeland Brenna , Johnson Jeremiah X
Published: August 2019

Shared stand-up electric scooters are now offered in many cities as an option for short-term rental, and marketed for short-distance travel. Using life cycle assessment, we quantify the total environmental impacts of this mobility option associated with global warming, acidification, eutrophication, and respiratory impacts. We find that environmental burdens associated with charging the e-scooter are small relative to materials and manufacturing burdens of the e-scooters and the impacts associated with transporting the scooters to overnight charging stations. The results of a Monte Carlo analysis show an average value of life cycle global warming impacts of 202 g CO2-eq/passenger-mile, driven by materials and manufacturing (50%), followed by daily collection for charging (43% of impact). We illustrate the potential to reduce life cycle global warming impacts through improved scooter collection and charging approaches, including the use of fuel-efficient vehicles for collection (yielding 177 g CO2-eq/passenger-mile), limiting scooter collection to those with a low battery state of charge (164 g CO2-eq/passenger-mile), and reducing the driving distance per scooter for e-scooter collection and distribution (147 g CO2-eq/passenger-mile). The results prove to be highly sensitive to e-scooter lifetime; ensuring that the shared e-scooters are used for two years decreases the average life cycle emissions to 141 g CO2-eq/passenger-mile. Under our Base Case assumptions, we find that the life cycle greenhouse gas emissions associated with e-scooter use is higher in 65% of our Monte Carlo simulations than the suite of modes of transportation that are displaced. This likelihood drops to 35%–50% under our improved and efficient e-scooter collection processes and only 4% when we assume two-year e-scooter lifetimes. When e-scooter usage replaces average personal automobile travel, we nearly universally realize a net reduction in environmental impacts.
Correlation and coherence analysis between sea surface temperature (SST) and surface wind in the Equatorial Western Sumatra Waters
Authors: Hatmaja R B , Wisha U J , Radjawane I M , Tanto T Al
Published: August 2019

Equatorial Western Sumatra Waters have a tremendous dynamic in ocean characteristics. It directly faces the Indian Ocean exactly located below the equator. Consequently, Equatorial Western Sumatra waters are influenced by the tropical climatic factors such as monsoons and climate variabilities, such as Indian Ocean Dipole (IOD) and Madden Julian Oscillation (MJO) that control sea surface temperature (SST) fluctuation in the Indian Ocean regions. This study aimed to review the correlation and coherence of SST distributed by surface wind in the Equatorial Western Sumatra waters. Wavelet method (cross wavelet transforms and wavelet coherence) was used to analyze the correlation and coherency between SST and surface wind. The annual variation of SST for 365 days period is the strongest event throughout the year caused by either monsoon or the changes of wind speed in the surface. Otherwise, the strongest intra-seasonal SST variation of 35 - 60 days observed from December 2012 to March 2013. The highest surface wind speed occurs in the southern and western waters. The surface wind plays a role in evoking SST distribution of 35 - 60 days period (intra-seasonal variability). Besides, the surface wind with 6 months period (semi-annual variability) influences the SST distribution which is identified only in the southern waters and the Indian Ocean regions. These conditions are possibly predicted as the influence of monsoons.
Diurnal variation of stable isotopes in rainfall observed at Bengkulu for the YMC-Sumatra 2017
Authors: Ichiyanagi K , Suwarman R , Belgaman H A , Tanoue M , Uesugi T , Warjono
Published: August 2019

Diurnal variability of stable isotopes in precipitation and its controlling factors are poorly understood, especially in the tropics. This study investigated the diurnal variability of stable isotopes in rainfall observed at Bengkulu in southern Sumatra, Indonesia. Rainfall samples were collected at 6-h intervals from 1 December 2017 to 15 January 2018 for the Year of the Maritime Continent (YMC-Sumatra 2017). The oxygen and hydrogen isotopic compositions δ18O and δH) of the rainwater varied from –15.1%o to –1.8%o and from –108.9%o to –1.3%o, respectively, and the d-excess varied from 1.9%o to 17.1%o. The observations at Bengkulu revealed that diurnal variation in rainfall amount was not significant for the entire period; however, the δ18O was lighter in both the early morning and the afternoon and heavier before noon and overnight. The δ18O became gradually depleted in the periods of continuous rain that occurred during 1–4 and 21–24 December. The amount of morning rain was much greater than evening rain in these periods, whereas the amount of evening rain was greater than morning rain in other periods. Based on satellite-derived CMORPH data, it is assumed that morning rain and evening rain corresponded to weak rainfall over surrounding sea region and strong rainfall over inland regions of Sumatra, respectively. The differences in moisture source and ratio of stratiform/convective rain rate between morning and evening might affect the isotopic composition of rainfall in the tropics.
The Effect of an Active Phase of the Madden-Julian Oscillation on Surface Winds over the Western Coast of Sumatra Island
Authors: Wu P , Ardiansyah D , Mori S , Yoneyama K
Published: August 2019

This study examined the effect of an active phase of the Madden-Julian Oscillation (MJO) on surface winds over the western coast of Sumatra Island using surface meteorological observations, meteorological radar observations, and balloon sounding data obtained from the Years of the Maritime Continent (YMC) Sumatra 2017 field campaign. Wind gusts (sudden and large increases in surface wind speed with durations of several to tens of minutes; squall) were observed frequently at Bengkulu from late November to early December 2017 during a local active phase of the MJO. The wind gusts occurred simultaneously with heavy precipitation when the eastward propagating convection from the Indian Ocean moved over the observation site. Upper air observations showed strong northwesterly winds in the lower troposphere in the 1,000–4,000 m layer. The surface wind gusts extended from the surface up to an elevation of 560 m, with the highest wind speed occurring approximately 300 m above the ground. Small changes in surface air pressure were observed during the wind gusts. The results suggested that momentum transfer from the upper atmosphere by downdrafts was the main cause of the surface wind gusts on the western coast of Sumatra Island during an active phase of the MJO.
Characteristic of anabatic wind in Bandung basin observed by AWS
Authors: Kombara P Y , Junnaedhi I D G A , Riawan E
Published: August 2019

A field campaign has been done for the wet season in 2015 to identify the pattern of local circulation such as anabatic wind at Bandung basin. In this field campaign, the Automatic Weather Stations (AWS) were installed at seven points from the north until the south region of Bandung basin. The result of this research defines the pattern of anabatic wind in Bandung basin into three categories: the pattern on weak convection, strong convection, and strong convection with rain event. On weak convection condition, after 12.00 LT, the anabatic wind tended to move to the north region of Bandung basin. The wind still moved to the north and south region, on strong convection and strong convection with rain event condition after 12.00 LT. However, after 15.00 LT the wind on strong convection with rain event changed to become northward. On strong convection and strong convection with rain event, the pattern of anabatic wind was influenced by the convective activity in the north and south region of Bandung basin. Whereas on weak convection condition, the pattern of anabatic wind was not influenced by the convective activity.
The evaluation of drought indices: Standard Precipitation Index, Standard Precipitation Evapotranspiration Index, and Palmer Drought Severity Index in Cilacap-Central Java
Authors: Balbo F , Wulandari R A , Nugraha M R R , Dwiandani A , Syahputra M R , Suwarman R
Published: August 2019

The Cilacap Regency-Central Java, is the largest agricultural area with a high level of drought vulnerability. This study aims to evaluate three indices in quantifying a drought condition in Cilacap Regency and its application in forecasting. The indices that were used in this study are Standard Precipitation Index (SPI), Standard Precipitation Evapotranspiration Index (SPEI), and Palmer Drought Severity Index (PDSI). The comparison between SPI and SPEI shows that there is no significant difference in terms of determining the drought severity. SPEI should be used when there is a temperature difference more than 2°C in 30 years. PDSI may provide more frequency of drought event and a good result in indicating the effects of drought on agricultural productivity. We used Climate Forecast System Version 2 (CFSv2) to predict drought severity by SPI. The result of model prediction shows that there is no significant improvement in accuracy before and after statistical bias correction. The prediction can be done on three months (lead3) before initial planting.
Preliminary result of characteristic of convective cloud development observed by x-band meteorological radar in bandung basin
Authors: Syaraswati R A , Trilaksono N J , Nugroho G A
Published: August 2019

The initial, mature, and dissipation stage changes in a convective cloud development have a short period of time so that the development stage analysis is needed by using data that has a high temporal resolution. The data that used are product CAPPI-V and CAPPI-Z from X-Band meteorological radar and also BBWS Citarum rainfall data from 13 stations that scattered in the area of Bandung basin. The selection of rainfall days is done to take the areas that have a strong convective system, and the result is that Sapan area has higher rainfall than 12 other stations on April 27th, 2017. The precipitation is caused by convective clouds. The initial stage of convective clouds begins with the existence of convergence phenomena in the afternoon and at 10 minutes before the rainfall event. It is also when there are maximum rainfall events on April 27th, 2017 which can indicate the formation of convective clouds. After the formation, the development stage occurs when there is an increase in reflectivity values on the radar and then convective cloud size starts to grow. When convective cloud size is dissipating, there is an identification of a decrease in reflectivity of the previous value in the evening. There is a new convective initiation next to the cloud that is in the dissipation stage and then joins to develops in a short time for about 30 minutes.
Identification of Mesoscale Convective Complex (MCC) Over Bangka Belitung Area
Authors: Saragih R W , Hestiwi A H , Sari F N Indah , Winarso PA
Published: August 2019

Mesoscale Convective Complex (MCC) is a mesoscale cloud convective system characterized by large, long-lived and quasi-circular pattern. The existence of MCC may trigger extreme weather events such as heavy rains which cause floods and landslides around the center of interest area. This paper aims to identify the presence of a storm cloud system which is observed as the MCC. For that purpose, this study used Himawari-8 satellite infrared channel data. Case of the study is the rain event in Bangka Belitung on 8 February 2016 which recorded 183.9 mm rainfall a day. Satellite data was processed using image processing software by applying MCC cloud system identification algorithm based on its physical characteristics, i.e. peak cloud temperature, coverage area, central point of cloud, cloud eccentricity and ellipse fitting, and lifetime of the cloud system. The final result of this study is able to yield the coordinates of latitude and longitude of MCC location, which are MCC cloud systems appeared around Bangka Belitung. This result confirmed that the occurrence of heavy rain on February 8th, 2016 in Bangka Belitung was caused by the presence of MCC around the interest area.
Analysis of ultraviolet index, ultraviolet B insolation, and sunshine duration at Bandung in year 2017
Authors: Hamdi S.
Published: August 2019

Ultraviolet index, ultraviolet B insolation, and sunshine duration in 2017 have been analyzed at Bandung, Indonesia (106.6 W and 6.9 S). The daily maximum ultraviolet B insolations have been grouped in ten-daily sequence following BMKG’s method in determining of dry/rainy season. Ultraviolet index classified following small modification WHO’s classification. Sunshine durations are clustered in 3 levels of exposure. It is found the average of sunshine duration in range 4.1-8 hours/day has 50% occurrence in 2017, meanwhile ultraviolet index more than 10 have been recorded in 46% occurrence in 2017, even of average of maximum ultraviolet B insolation is about 1.22 W/m2, and maximum intensity on 2017 is 2.17 W/m2. Both of ultraviolet index and maximum ultraviolet B insolation have a similar pattern on 2017 and the minimum value is on aphelion.