cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Improvement of Tread brake Heat Dissipation Using Forced Air Cooling
Creators: name: Berhe, Hishe
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2015

description: Sufficient heat dissipation is crucial to the effective operation of friction based braking systems. Such cooling is generally provided by ensuring a sufficient supply of cooling air to the heated components, hence the aerodynamics in the region of the brake components is extremely important. The objective of the research was to develop an understanding of how forced air vented from the brake pipe and main reserviore could be used to improve the cooling of train tread brake. The thermal analyses of tread brake during emergency braking at a speed of 100 km/h considering forced air cooling were investigated using finite element (FE) and computational fluid dynamics (CFD) methods. The results suggested that the higher convection coefficients achieved with forced air cooling will not only reduce the maximum temperature in the braking but also reduce the thermal gradients, since heat will be removed faster from hotter parts of the tread brake. Forced air cooling should be effective to reduce the risk of hot spot formation and tread wheel thermal distortion. The highest temperature after emergency braking was 432.43 °C and 412.75 °C , 399.13 °C and 384.81°C without and with considering forced air cooling with velocities of (50,100 and 150 m/s) , respectively. The main purpose of this study is to improve the heat dissipation of tread brake by using forced air cooling from the brake pipe and main reservoir.
title: Insights into the skeletal growth of massive corals from the central Belize Barrier Reef (Central America): Results from high-resolution skeletal density variations in Orbicella faveolata
Creators: name: Zoppe, Simon Felix
name: Deveaux, Michael
name: Gischler, Eberhard
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
Massive reef-forming corals (Scleractinia) are biological and palaeoclimatological archives, based on their skeletal growth chronology that is characterized by annual density bandings (analogue to dendrochronology). A limitation in coral sclerochronology is the quantification of skeletal density due to the need of precise analytical techniques. This study deals with the application of two-dimensional grid-scanning gamma densitometry (241Americium-radiation beam technique) to quantify skeletal density fluctuations at higher spatiotemporal (intra-annual) resolution. An advantage of this method is a reduction of local influences along the coral growth axis (e.g., pore spaces, calyx architecture), comparative to previous one-dimensional track selection techniques with gamma densitometry. The widespread Atlantic coral Orbicella (ex Montastraea) faveolata was used as a representative massive coral species. A colony from the central Belize Barrier Reef (BBR, Central America) was analysed, yielding 1005 calibrated density values corresponding to a skeletal growth period of 38 years (1962-1999 CE). An average of 27.6±3.5 measurements per growth increment translates into a roughly biweekly resolution for selected grid point rows. The colony shows a long-term decline in skeletal density, accompanied by reduced rates in carbonate accretion. This implies limited capability for skeletal formation in O. faveolata corals within the central BBR. Annual density bandings are likely connected to intra-annual fluctuations in δ13C isotope composition, suggesting a relationship to their mixotrophic lifestyle with a carbon uptake either by heterotrophic feeding and/or photosynthetic activity of their endosymbiotic zooxanthellae. However, combined data suggest a more complex influence of environmental and biological controls on skeletal density variations in the present coral.
Monopole excitation of the Hoyle state and linear-chain state in 12C
Creators: name: Funaki, Yasuro
Publisher: name: arXiv
Year: 2016
Subjects: subject: Nuclear Theory (nucl-th)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: Background: Two new $J^π=0^+$ states are recently observed around a few MeV above the Hoyle state (the second $0^+$ state in 12C). The characters of them are only poorly discussed in theory and are still mysterious. Purpose: I give for the first time a comprehensive understanding of the structures of the $0^+$ states by analyzing their wave functions, and discuss relationship with the Hoyle state, similarities, and differences between the states. Method: I extend a microscopic $α$-cluster model called Tohsaki-Horiuchi-Schuck-Röpke (THSR) wave function so as to incorporate $2α+α$ asymmetric configuration explicitly. The so-called $r^2$-constraint method to effectively eliminate spurious continuum components is also used. Results: The $0_3^+$ state is shown to have a very large squared overlap with a single configuration of the extended THSR wave function in an orthogonal space to the Hoyle state as well as to the ground state. The $0_4^+$ state has a maximal squared overlap with a single extended THSR wave function with an extremely prolately-deformed shape. Conclusions: The $0_3^+$ state appears as a family of the Hoyle state to have a higher nodal structure in the internal motions of the $3α$ clusters, due to the orthogonalization to the Hoyle state. The $0_4^+$ state dominantly has a linear-chain structure, where the $3α$ clusters move freely in a non-localized way, like a one-dimensional gas of the $3α$ clusters.
description: 8 pages, 8 figures, 1 table, and the title is slightly changed. To be published in PRC
Multiscale method, Central extensions and a generalized Craik-Leibovich equation
Creators: name: Yang, Cheng
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mathematical Physics (math-ph)
subject: Dynamical Systems (math.DS)
subject: Symplectic Geometry (math.SG)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: In this paper we develop perturbation theory on the reduced space of a principal $G-$bundle. This theory uses a multiscale method and is related to vibrodynamics. For a fast oscillating motion with the symmetry Lie group $G$, we prove that the averaged equation (i.e. the equation describing the slow motion) is the Euler equation on the dual of a certain central extension of the corresponding Lie algebra $\mathfrak g$. As an application of this theory we study the Craik--Leibovich (CL) equation in hydrodynamics. We show that CL equation can be regarded as the Euler equation on the dual of an appropriate central extension of the Lie algebra of divergence-free vector fields. From this geometric point of view, one can give a generalization of CL equation on any Riemannian manifold with boundary. For accuracy of the averaged equation, we prove that the difference between the solution of the averaged equation and the solution of the perturbed equation remains small (of order $ε$) over a very long time interval (of order $1/{ε^2}$). Combining the geometric structure of the generalized CL equation and the averaging theorem, we present a large class of adiabatic invariants for the perturbation model of the Langmuir circulation in the ocean.
description: 24 pages
title: Dissecting the Sadisdorf Sn-W-Li vein and greisen system
Creators: name: Leopardi, Dino
name: Gutzmer, Jens
name: Lehmann, Bernd
name: Burisch, Mathias
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
The Sadisdorf Sn-W-Li-Cu prospect, Germany, comprises magmatic-hydrothermal greisen and vein-style mineralization associated to a small alkali-feldspar granite porphyry. Petrographic and fluid inclusion data across the full extent of the deposit is used to understand the temporal and spatial evolution of the mineral system and the key factors controlling ore formation.

Four mineral associations have been recognized from proximal to distal to the intrusive stock. These are hosted within quartz-mica veins or greisen bodies: 1) oxide-dominant cassiterite-wolframite-molybdenite association, 2) cassiterite-(stannite) associated with Cu-Zn-Pb-As sulfides mixed association, 3) sulfide-dominant chalcopyrite-sphalerite-galena-arsenopyrite-tennantite-pyrite association, and 4) late-stage fluorite veins and cavity infill.

Fluid inclusions (FI) in quartz, topaz, cassiterite and sphalerite consist of H2O-NaCl or H2O-NaCl-CO2±CH4 fluids. Irrespective of association most FI show the same range in homogenization temperatures (Th; 202-420°C) and salinities (0-13 wt.% NaCl eq.). FI hosted by late-fluorite, however, are marked by lower Th (<269°C) and salinities (0-5 wt.% NaCl eq.).

Results imply that the ore fluid was a low-salinity and high-temperature vapor-rich fluid. Despite the distinct mineralogical zoning within the system, significant spatial variations of temperature or salinity could not be identified. Hence, we propose that zoning is a result of systematic variations in oxygen fugacity and/or availability of reduced sulfur along the fluid flow path, either attributed to consumption of oxygen by early oxides, fluid-rock interaction and/or potential volatile loss. Conversely, the lower salinity and temperatures of the late fluorite association reflects the dilution and cooling of fluids with time and likely the ingress of meteoric water into the system.
ВЛИЯНИЕ КОРОНАВИРУСНОГО КРИЗИСА НА АВИАЦИОННЫЕ ТРАНСПОРТНЫЕ УСЛУГИ В РОССИИ
Creators: name: Сообщество рецензентов Международного научно-исследовательского журнала
Publisher: name: ИП Соколова М.В.
Year: 2022
Subjects: кризис пандемии
авиационные транспортные услуги
воздушный транспорт
транспортные перевозки
гражданская авиация
авиационная отрасль
авиационные компании.

description: Международный научно-исследовательский журнал, №8(122) (2022)
Total nonnegativity and stable polynomials
Creators: name: Purbhoo, Kevin
Publisher: name: arXiv
Year: 2016
Subjects: subject: Complex Variables (math.CV)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 32A60 (Primary), 14M15, 14P10, 15B48 (Secondary)

description: We consider homogeneous multiaffine polynomials whose coefficients are the Plücker coordinates of a point $V$ of the Grassmannian. We show that such a polynomial is stable (with respect to the upper half plane) if and only if $V$ is in the totally nonnegative part of the Grassmannian. To prove this, we consider an action of matrices on multiaffine polynomials. We show that a matrix $A$ preserves stability of polynomials if and only if $A$ is totally nonnegative. The proofs are applications of classical theory of totally nonnegative matrices, and the generalized Pólya-Schur theory of Borcea and Brändén.
description: 13 pages
A study of microvoid formation on metal cutting [microform]
Creators: name: Luong., H. S.
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
title: The role of S3•- in molybdenum transport by hydrothermal fluids revealed by in situ X-ray absorption spectroscopy
Creators: name: Kokh, Maria A.
name: Borchert, Manuela
name: Klemme, Stephan
name: Schmidt, Christian
name: Hazemann, Jean-Louis
name: Testemale, Denis
name: Aguilar, Antonio
name: Bazarkina, Elena F.
name: Moeller, Christoph
name: Laskar, Clément
name: Pokrovski, Gleb S.
name: Wilke, Max
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
The knowledge of molybdenum speciation under hydrothermal conditions is a key for understanding the formation of porphyry deposits which are the primary source of Mo. Previous studies have revealed a complex speciation of Mo including (hydrogen)molybdate ions, their ion pairs with alkalis, oxy-chloride species, and thiomolybdate complexes. However, these available data are unable to account for the observed massive transport of Mo in porphyry-related fluids revealed by fluid inclusion analyses demonstrating 100s ppm of Mo (e.g., Kouzmanov and Pokrovski, 2012). A potential missing ligand for Mo may be the trisulfur radical ion, which is predicted to be abundant in sulfate-sulfide rich acidic-to-neutral porphyry-like fluids.

We performed X-ray absorption spectroscopy (XAS) measurements at the Mo K-edge (20.0 keV) in a hydrothermal autoclave available at BM30 of ESRF synchrotron (Testemale et al., 2005) to study the molybdenite solubility in model S3•- rich aqueous solutions at 300°C and 500 bar. We found that Mo can be efficiently transported by S3•--bearing fluids at concentrations of several ppm, whereas the available data on OH-Cl-S complexes predict negligibly small (<100 ppb) Mo concentrations at our conditions. Work is in progress to extend the experiments to wider T-P-composition range of porphyry fluids and to quantitatively assess the role of S3•- in Mo transport by geological fluids.

K. Kouzmanov and G.S. Pokrovski, Soc. Econ. Geol. Spec. Pub. 16 (573–618), 2012; D. Testemale et al., Rev. Sci. Instr. 76 (043905), 2005.

Funding: Deutsche Forschungsgemeinschaft WI 2000/25-1, KL 1368/13-1, SCHM 2415/6-1, ESRF ES-1050.
Superspecial curves of genus $4$ in small characteristic
Creators: name: Kudo, Momonari
name: Harashita, Shushi
Publisher: name: arXiv
Year: 2016
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: This paper contains a complete study of superspecial curves of genus $4$ in characteristic $p\le 7$. We prove that there does not exist a superspecial curve of genus $4$ in characteristic $7$. This is a negative answer to the genus $4$ case of the problem proposed by Ekedahl [9] in 1987. This implies the non-existence of maximal curve of genus $4$ over $\mathbb{F}_{49}$, which updates the table at {\tt manypoints.org}. We give an algorithm to enumerate superspecial nonhyperelliptic curves in arbitrary $p \ge 5$, and for $p\le 7$ we excute it with our implementation on a computer algebra system Magma. Our result in $p=5$ re-proves the uniqueness of maximal curves of genus $4$ over $\mathbb{F}_{25}$, see [11] for the original theoretical proof. In Appendix, we present a general method determining Hasse-Witt matrices of curves which are complete intersections.
description: Corollary 5.1.3 and Appendix B have been added
Failure analysis of signaling system of Addis Ababa-Light Rail Transit
Creators: name: Yosef, Bekele
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2015

description: Railway signaling system is one of the most important parts of the many which make up the railway system. It is the vital control system which demands the use of reliable and fault tolerant system as it directly related to the safe movement of passenger trains. Ensuring safety in railway signaling systems is considered as significant as a guarantee of the safe and efficient operation of the whole railway. In fact, one of the most important objectives of a safety analysis of the signaling system is to maintain a high degree of safety. Therefore, to avoid these problems and provide an optimized signaling, a signaling system design should incorporate additional safety analysis. One of the safety analysis methods from design stage is failure analysis which is used to study the whole dynamic system, point out potential failure modes, failure propagation scheme and used to predict about the system. To this end, this thesis presents the failure analysis of Addis Ababa-Light Rail Transit signaling system by employing model-based failure analysis methods and system fault tree, causes and effects, major failures are investigated. Failure propagation models for the subsystems of AA-LRT signaling system are modeled on Matlab-Simulink, where signaling equipments in a main station are represented. Functional interactions between those equipments are also represented. Hierarchically Performed Hazard Origin and Propagation Studies (HiP-HOPS) is used from the most common model-based safety analysis tools to define each signaling system equipment local failure data and to analyze failure models which are done on Simulink. Fault trees are generated as a result for selected hazards in simulations showing the possible causes of failures.
title: Insight into formation of hydrothermal ore deposits using a hydrothermal autoclave and X-ray absorption spectroscopy
Creators: name: Borchert, Manuela
name: Kokh, Maria
name: Wilke, Max
name: Louvel, Marion
name: Valsera Moreno, Pilar
name: Al Abed, Rami
name: Morgenroth, Wolfgang
name: Schmidt, Christian
name: Testemale, Denis
name: Welter, Edmund
name: Klemme, Stephan
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
Hydrothermal fluids play an important role during the formation of most economically explored ore deposits. While cycling through the crust these supercritical fluids efficiently dissolve and transport metals from the source rocks; metal-rich minerals precipitate on their way towards the Earth’s surface. In general, compositions of hydrothermal ore fluids are well known, e.g., by analyzing fluid inclusions in ore minerals. However, because sources and physiochemical characteristics of hydrothermal fluids vary widely, complexation and speciation of metals in the fluid and precipitation mechanisms of ore minerals are still matter of controversial debates. Conclusions on metal complexation and speciation in the fluids are usually based on analysis of quench experiments that do not consider the probably non-quenchable nature of hydrothermal metal complexes e.g., as previously reported for gold (Pokrovski et al., 2015). Thus, reliable information on metal complexation and speciation during ore deposit formation can only be obtained using in-situ data.

Here, we present an autoclave dedicated to in-situ characterization of hydrothermal fluids at high pressures and temperatures at Deutsches Elektronen-Synchrotron (Klemme et al., 2021). Besides discussing details of the experimental set-up we will also focus on results of two ongoing projects dedicated to formation of W and Sn hydrothermal ore deposits.

G. Pokrovski et al., PNAS 112 (44), 2015; Klemme et al., Rev Sci Instr, 92, 2021

Funding: Bundesministerium für Bildung und Forschung (BMBF) grant FKZ 05K16PMA, DESY Center for Molecular Water Science - Early Science Project.
Controlled variation of the refractive index in ion-damaged diamond
Creators: name: Olivero, P.
name: Calusi, S.
name: Giuntini, L.
name: Lagomarsino, S.
name: Giudice, A. Lo
name: Massi, M.
name: Sciortino, S.
name: Vannoni, M.
name: Vittone, E.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A fine control of the variation of the refractive index as a function of structural damage is essential in the fabrication of diamond-based optical and photonic devices. We report here about the variation of the real part of the refractive index at lambda=632.8 nm in high quality single crystal diamond damaged with 2 and 3 MeV protons at low-medium fluences (10^13 - 10^17 ions cm^-2). After implanting the samples in 125x125 um^2 areas with a raster scanning ion microbeam, the variation of optical thickness of the implanted regions was measured with laser interferometric microscopy. The results were analyzed with a model based on the specific damage profile. The technique allows the direct fabrication of optical structures in bulk diamond based on the localized variation of the refractive index, which will be explored in future works.
description: 15 pages, 4 figures
Tinjauan Yuridis Tindak Pidana Perdagangan Orang (Human Trafficking) (Studi Kasus Di Kabupaten Sumba Barat Daya-NTT)
Creators: name: Adriana Kaka, Rambu Susanti Mila Maramba, Rambu Hada Indah
Publisher: name: Zenodo
Year: 2024

description: Perdagangan manusia atau human trafficking menjadi fenomena mendunia karena sistemnya terorganisisr. Jaringannya amat rapih, banyak modus operandi human trafficking saat ini, salah satunya di Sumba modusnya menjadi pekerja rumah tangga, kerja di kebun sawit. Tujuan penelitian ni adalah ntuk mengetahui dan menganalisis penegakan dan penerapan hukum terhadap korban Perdagangan orang (human trafficking) di Kabupaten Sumba Barat Day. Penelitian ini menggunakan jenis penelitian Hukum Normati-Empiris (Applied Law Research) yaitu berupa gabungan dari studi kasus Hukum Normatif-Empiris berupa produk perilaku Hukum. Pendekatan yang digunakan adalah Pendekatan Undang-Undang (statute approach), Pendekatan kasus (case approach) dan pendekatan konseptual. Secara eksplisit maupun implisit peraturan mengelompokkan perdagangan manusia sebagai bentuk pelanggaran HAM yang harus diberantas. Dalam deklarasi HAM sedunia disetujui oleh Resolusi Majelis Umum PBB No. 217 A (III) pada 10 desember 1948 di Paris Prancis, pada Pasal 4 UDHR dengan tegas dikatakan, tak seorangpun boleh diperbudak atau diperhambakan, segala bentuk perbudakan dan perdagangan budak harus dilarang.  Jelas dalam konteks perdagangan orang hal tersebut harus diberantaskan dari muka bumi ini, terkususnya di Sumba Barat Daya. Pasal 297 KUHP mengancam perdagangan perempuan dan anak diancam dengan pidana penjara paling lama enam tahun. peraturan mengenai kejahatan perdagangan orang tentu bertujuan untuk melindungi harkat dan martabat manusia sebagai manusia yang bebas dari kesewenangan manusia lain sehingga kodrat manusia sebagai makhluk ciptaan Tuhan yang sempurna dan berakal budi terjamin oleh peraturan yang ada. Maraknya perdagangan manusia yang terjadi salah saru faktornya terdapat pada penegakan hukum yang kurang optimal dalam penanganan pelaku kejahatan perdagangan manusia untuk ditelusuri sampai keakar akarnya.
title: On the genesis of post-subduction porphyry copper magmas
Creators: name: Chang, Jia
name: Audetat, Andreas
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
For subduction-related porphyry Cu deposits, it is generally agreed that the ore-forming magmas fractionate from mafic magmas produced by slab fluid±melt-fluxed melting of the asthenospheric mantle wedge. This model, however, is not able to explain post-subduction porphyry Cu deposits that formed after the termination of slab subduction. Popular models suggest that post-subduction porphyry Cu magmas are partial melts of former lower crustal sulfide-rich arc cumulates with or without minor contribution from potassic mafic magmas. Here we re-appraise this model via a combined approach of natural sample studies and piston-cylinder experiments. The Sanjiang region of SW China is a typical post-subduction porphyry Cu metallogenic belt that formed during the India-Asia continental collision. Based on a detailed petrographic study, we investigated whole-rock elemental and Nd-Sr-Pb isotopic compositions of variously evolved magmatic rocks and garnet-bearing xenoliths throughout the southern Sanjiang region. The results demonstrate that the continental collision-related porphyry Cu magmas formed solely by fractionation of potassic mafic magmas, and that the lower crustal partial melting model built upon wrong radiogenic isotopic compositions of the investigated garnet-bearing xenoliths. The potassic mafic magma fractionation model is further supported by crystallization experiments using a basaltic trachyandesite sample as starting material. The experimental run products reproduce not only the mineral crystallization sequence of magmatic rocks in the southern Sanjiang region but also the liquid line of descent defined by the whole-rock data. Hence, we suggest that the role of pre-existing lower crustal arc cumulates in forming post-subduction porphyry Cu magmas has been greatly overestimated.
title: The controls on sedimentary pyrite formation in Southern Ocean deep-sea sediments
Creators: name: Mikler, Monika
name: Weber, Michael
name: Franz, Sven Oliver
name: März, Christian
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
The formation of pyrite in deep-marine sediments is typically limited by organic carbon or/and reactive iron availability. The Southern Ocean generally exhibits an iron deficiency, limiting bioproductivity and thus the sequestration of CO2 from the atmosphere. Based on iron deficiency in the photic zone, it could be assumed that the formation of pyrite is iron-limited, too.

To evaluate the controls on sedimentary pyrite formation, sediments from ca. 4 Ma to recent, recovered during IODP Expedition 382 (Iceberg Alley) in the Scotia Sea, were examined for their carbon, nitrogen, sulfur, major and minor element contents.

The organic carbon and sulfur contents in the sediments have a mean value of c. 0.4 and 0.3 wt.%, respectively, whilst iron has a mean value of c. 4 wt.%. Organic carbon and sulfur demonstrate a good correlation and a significant increase from c. 1.25 Ma toward the stratigraphically younger. Further, the relationship between iron, sulfur, and organic carbon suggests that sulfur is fixed in pyrite.

The good correlation between sulfur and organic carbon points to a organic carbon limitation for pyrite formation. Also, the excess of iron speaks against an iron limitation for pyrite formation. Therefore, the increase in sulfur and organic carbon contents from the onset of the mid-Pleistocene transition might demonstrate higher export of organic carbon from the photic zone to the ocean floor, and an enhanced formation of pyrite in the sediments.
Fault detection, diagnosis and prognosis using Grey System theory
Creators: name: Luo., Mingfei
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Core-EP Decomposition and its Applications
Creators: name: Wang, Hongxing
Publisher: name: arXiv
Year: 2016
Subjects: subject: Rings and Algebras (math.RA)
subject: FOS: Mathematics

description: In this paper, we introduce the notion of the core-EP decomposition and some of its properties. By using the decomposition, we derive several characterizations of the core-EP inverse, introduce a pre-order(i.e. the core-EP order) and a partial order(i.e. the core-minus partial order), and characterize the properties of both orders.
Influence of the iron spin crossover in ferropericlase on the lower mantle geotherm
Creators: name: Valencia-Cardona, Juan J.
name: Shukla, Gaurav
name: Wu, Zhongqing
name: Houser, Christine
name: Yuen, David A.
name: Wentzcovitch, Renata M.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: The iron spin crossover in ferropericlase introduces anomalies in its thermodynamics and thermoelastic properties. Here we investigate how these anomalies can affect the lower mantle geotherm. The effect is examined in mantle aggregates consisting of mixtures of bridgmanite, ferropericlase, and CaSiO$_3$ perovskite, with different Mg/Si ratios varying from harzburgitic to perovskitic (Mg/Si$\sim$1.5 to 0.8). We find that the anomalies introduced by the spin crossover increase the isentropic gradient and thus the geotherm proportionally to the amount of ferropericlase. The geotherms can be as much as $\sim$ 200K hotter than the conventional adiabatic geotherm at deep lower mantle conditions. Aggregate elastic moduli and seismic velocities are also sensitive to the spin crossover and the geotherm, which impacts analyses of lower mantle velocities and composition.
title: Structural investigations on iron-ore sinter phases – crystallography meets applied mineralogy
Creators: name: Kahlenberg, Volker
name: Krüger, Hannes
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
Sinter plants are an integral part for the preparation of iron ores for the blast furnace process. In a series of complex reactions, semi-molten, centimeter-sized aggregates are formed containing ore particles cemented by a matrix of Ca-rich ferrites that contain some silica and alumina. For these compounds, the acronym SFCA (Silico-Ferrites of Calcium and Aluminum) was coined. The SFCA phases with general composition A14+6nO20+8n (A: Ca, Mg, Fe2+, Fe3+, Al3+, Si4+) act as the binder that keeps the sinters intact in order to withstand the loads in a blast furnace.

Depending on the value of n in the chemical formula, four different SFCA-phases can be distinguished forming a polysomatic series. They can be described with a modular approach involving the stacking sequence of “P” and “S” modules that can be imagined as being cut from the well-known pyroxene and spinel structure-types. The representatives with n = 0 (A14O20) are related to the sapphirine supergroup of minerals.

Even though the SFCAs are critical for the production of iron-ore sinters, it is surprising that there are still many open questions regarding their composition, atomic structure, thermochemistry and stability. For any target-oriented improvement and optimization of ore-sintering as well as thermodynamic modeling of the sinters, a much more detailed understanding of these fundamental solid-state properties of the SFCAs is essential. The present contribution provides - for the first time - a detailed crystallographic analysis on the impact of chemical variations on these compounds that are of relevance for the field of applied mineralogy.
―Removal of Lead from Waste Water Using Corn Cob Activated Carbon as An Adsorbent
Creators: name: Tesfaye, Debela
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2016

description: Industrial development has caused the release of various pollutants including heavy metals into the environment. These toxic compounds are extremely dangerous to living beings and the environment due to their non-biodegradability, severe toxicity, carcinogenicity, the ability to be accumulated in nature and the ability to contaminate groundwater and surface water. The aim of the present research was to provide an appropriate and cost-effective adsorbent to remove one of these heavy metals namely lead from waste water. The activated carbon was produced from the dried corn cob. Batch experiments were performed on synthetic samples at room temperature. The effect of pH, adsorbent dose, initial concentration, and contact time were studied, and the adsorption isotherms of heavy metals were determined. The optimum conditions for corn cobs activated carbon preparation were determined as impregnation ratio of 1.5, carbonization temperature of 450oC, activation time of 120min, and acid concentration 60% by weigh. The result of the characterization showed that the corn cob activated carbon has good properties as compared with other reference activated carbons. The maximum removal efficiency of heavy Pb2+ions by activated carbon adsorbent prepared from corn cobs was obtained optimum pH 5, optimum adsorbent dose of 3g, and the optimum contact time of 120 min; in these optimum conditions the removal efficiency was 96.8%. Greater adsorption amount of 10.7mg/g occurs at smaller adsorbent dose of 1g. The results were also confirmed that the adsorption process follows Langmuir isotherm model with a better sorption fit and supported for the monolayer adsorption of Pb+2ions on corn cobs activated carbon. The kinetic model of this study shows a pseudo-second order kinetic model with good correlation coefficient. Based on the results obtained, the activated carbon produced from corn cob has a good capability in removal of the lead ions from the aqueous solutions. Key words: corn cobs activated carbon; adsorption of lead (Pb2+); optimal conditions.
On the Benefit of Automated Static Analysis for Small and Medium-Sized Software Enterprises
Creators: name: Gleirscher, Mario
name: Golubitskiy, Dmitriy
name: Irlbeck, Maximilian
name: Wagner, Stefan
Publisher: name: arXiv
Year: 2016
Subjects: subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: Today's small and medium-sized enterprises (SMEs) in the software industry are faced with major challenges. While having to work efficiently using limited resources they have to perform quality assurance on their code to avoid the risk of further effort for bug fixes or compensations. Automated static analysis can reduce this risk because it promises little effort for running an analysis. We report on our experience in analysing five projects from and with SMEs by three different static analysis techniques: code clone detection, bug pattern detection and architecture conformance analysis. We found that the effort that was needed to introduce those techniques was small (mostly below one person-hour), that we can detect diverse defects in production code and that the participating companies perceived the usefulness of the presented techniques as well as our analysis results high enough to include the techniques in their quality assurance.
description: 25 pages, 0 figures
title: Melt-assisted strain localization in the upper mantle shear zone of northwestern Ronda (Spain)
Creators: name: Tholen, Sören
name: Linckens, Jolien
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
On the northwestern boundary of the world’s largest exposure of subcontinental mantle a major shear zone crops out. A microstructural transect from mylonites to tectonites (0‑700 m distance to the shear zone front) reveals a metasomatic history of multiple melt pulses with major impact on deformation and shear localization. Fe/Ti rich melts coming from a structurally deeper melting front inside the peridotite body, re‑fertilized the entire shear zone area up to its present-day front and precipitated interstitial pyroxenes and spinel. The resulting mixed matrix of recrystallized olivine and interstitial grains localized the deformation in the entire melt-affected region. Microstructural characteristics are elongated olivines with film/wedge-shaped pyroxenes along the olivine grain boundaries and interstitial spinel. Melt-rock reaction textures such as indentations, highly irregular grain shapes and lobate boundaries are commonly present. Strong CPOs (olivine A-type) for all phases and the absence of amphibole in the mixed matrix indicate deformation under relatively dry conditions predominantly accommodated by dislocation creep. However, P-T estimates (1‑2 GPa, 800‑900 °C), average grain sizes of ~100 µm and the localization of deformation in the mylonitic area also indicate the activity of an additional grain size sensitive mechanism. Within the matrix, reacting pyroxene porphyroclasts form tails of pyroxene, olivine, amphibole and spinel neoblasts. Their similar or coarser grain sizes compared to the matrix and an equiaxial grain shape indicate no further strain localization in these tails. Their predominant B- or AG- CPO-types of olivine and the presence of amphibole suggest the presence of fluids during the tail formation.
An experimental study of a rotary heat regenerator and rotary dehumidifiers
Creators: name: Luo., Dejin
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
title: Feedbacks in silicate glass alteration studied by in operando fluid-cell Raman spectroscopy
Creators: name: Müller, Gerrit
name: Fritzsche, Moritz Bernd Karl
name: Dohmen, Lars
name: Geisler, Thorsten
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
The alteration of silicate glasses (and minerals) is involved in most biogeochemical cycles and poses challenges in several technical applications. The mechanism(s), kinetics and rate-determining factors have been extensively studied in an attempt to eventually arrive at a quantitative, predictive process description. However, this has proven challenging, because of the non-linear progression of the alteration process, which is affected by several reaction-inherent feedbacks. We investigated the interplay of such feedbacks through Raman spectroscopic fluid-cell experiments, enabling in operando visualization and rate measurements of reactions at the altering glass surface. One experiment with a low surface area-to-solution volume (SA/SV) ratio exhibited a transient acceleration of initial dissolution rates, followed by continuously rapid glass dissolution along with slow growth of a smectite-based surface alteration layer (SAL), apparently limited by glass-derived Mg. Contrastingly, in a high SA/SV experiment, glass dissolution monotonically decreased after the onset of rapid SAL growth, which was followed by the formation of carbonate coating and pore-space fillings, as well as by zeolite precipitation. Growth conditions and resulting properties of the SAL seem to exert dominant, non-linearly decelerating effects on glass dissolution, but are opposed by (re-)accelerating effects of glass cracking, pitting, and SAL delamination. In turn, SAL formation depends on precipitation kinetics and the accumulation of glass-derived solutes at the reaction front. However, dissolution and precipitation may also feedback with solution chemistry and transport processes. Such mechanistic insights from in operando experiments help understanding silicate alteration processes and can assist the improvement of predictive models.
Η ΣΥΜΒΟΛΗ ΤΗΣ ΧΩΡΟΤΑΞΙΚΗΣ – ΠΟΛΕΟΔΟΜΙΚΗΣ ΜΕΤΑΡΡΥΘΜΙΣΗΣ ΣΤΗΝ ΠΕΡΙΦΕΡΕΙΑΚΗ ΑΝΑΠΤΥΞΗ
Creators: name: ΣΤΑΜΑΤΑΚΟΣ, ΠΑΝΑΓΙΩΤΗΣ
Publisher: name: Πανεπιστήμιο Πελοποννήσου
Year: 2022
Subjects: subject: ΧΩΡΟΤΑΞΙΑ - ΠΟΛΕΟΔΟΜΙΑ - ΠΕΡΙΦΕΡΕΙΑΚΗ ΑΝΑΠΤΥΞΗ

description: Μ.Δ.Ε. 312
description: Το αντικείμενο της παρούσας διπλωματικής εργασίας είναι η παρουσίαση του χωρικού σχεδιασμού στην Ελλάδα και ο τρόπος που συμβάλει στην περιφερειακή ανάπτυξη. Αναλυτικότερα, η δομή της εργασίας έχει ως εξής: Στο πρώτο κεφάλαιο γίνεται μια εισαγωγή στην έννοια του χωρικού σχεδιασμού και το διαχωρισμό του σε χωροταξικό και πολεοδομικό, καθώς και μια ιστορική αναδρομή στον ελληνικό χωρικό σχεδιασμό. Στο δεύτερο κεφάλαιο παρουσιάζονται οι μεταρρυθμίσεις του στρατηγικού σχεδιασμού, όπως αποτυπώνονται στην ισχύουσα νομοθεσία. Στο τρίτο κεφάλαιο παρατίθενται οι μεταρρυθμίσεις του ρυθμιστικού σχεδιασμού, σε ένα ευρύ νομικό φάσμα. Στο τέταρτο κεφάλαιο περιγράφονται τα περιφερειακά εργαλεία του χωρικού σχεδιασμού και ο τρόπος συμβολής του στην περιφερειακή ανάπτυξη. Τέλος, στο πέμπτο κεφάλαιο παρουσιάζονται τα συμπεράσματα που προέκυψαν από την εκπόνηση της διπλωματικής εργασίας.
Fatigue Crack Growth Analysis of the Light Rail Vehicle Braking Disc Under Different Braking Conditions Including Emergency Braking
Creators: name: Daniel, Liyew
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2019

description: Railway brake discs are the safety-critical components usually designed for up to ten years of operation. To guarantee the safety, fracture mechanics method is usually applied to perform the prediction of fatigue crack growth. The main purpose of this study is to analyze the stresses and fatigue crack propagation of disc brake under different speeds and load of AA-LRT train services. Mechanical and thermo-mechanical fatigue crack can often be found on the friction surface of brake discs used in railway vehicles after a period of usage due to exposure on heavy thermal and mechanical stress during braking and radial crack patterns that mostly occur. A brake disc crack exhibits different initiation and propagation behaviors with respect to different braking conditions. In this paper, the effect of braking energy on brake disc fatigue crack evolution is investigated by using a novel Extended Finite Element Method (XFEM) implemented in ABAQUS software for a train operating at acceptable and over speed at room temperature (25 o C) and at higher temperature (500 o C). Simulations at 4, 8, 12, 16 and 20mm crack length reveal that crack propagation the maximum effective stress intensity factor increase from as the crack length increased and accordingly the crack propagation rate increases at the crack size become large. On the other hand, the effect of temperature and speed were observed from the results to contribute to the increase of crack propagation for larger crack size. In all cases, over speed and high temperature, as the braking is applied repeatedly, lead to increased propagation rate of the crack on the friction surface of the disc.
The Effect of Multi-modal Cargo Transport System on the Efficiency of the Import Business in Ethiopia. Prepared
Creators: name: Assefa, Tadele
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2019

description: In general, transport sector has a significant effect on the international trade in terms of cost, and lead time. Especially, in the landlocked country like Ethiopia the effective and efficient management of multimodal transport operation has a positive and significant effect on the efficiency of foreign trade economy. This research conceptualizes and develops on four dimensions of multimodal cargo transport system (regulations, infrastructures, ICT applications and competence/skill) and tests the selected company employee's prospect on effect of multimodal cargo transport system on the efficiency of the import business in terms of cost and time. The data for the research was collected from 203 employees of 15 convenient companies. The relationships proposed in the framework were tested using Pearson correlation, and the causal relations were analyzed using regression analysis. From the result of the analysis it is concluded that there is strong relationship between multimodal transport system (the collective representative of the four dimensions) and import business efficiency (cost and time). Moreover, multimodal transport system (regulations, infrastructures, ICT applications and skill) has an influence on both total costs and lead time of the imported cargos. On the other hand, the total lead time has also an influence on the total cost of imported cargos. Therefore, in order to achieve effective and efficient multimodal operation and import business in both cost and time it is very important for the country to give due emphasis to the development of transport regulations, suitable infrastructures, appropriate & updated ICT applications and competent/skilled man power.
title: Σχεδιάζοντας μαθησιακά σενάρια ΤΠΕ σε πλαίσιο εξατομικευμένης μάθησης: Αξιοποιώντας το CPELDS
title: Designing ICT learning scenarios in the context of personalised learning: Utilizing CPELDS
titleType: AlternativeTitle
Creators: name: Ρίγκος, Δημήτριος
Publisher: name: Πανεπιστήμιο Δυτικής Αττικής
Year: 2023
Subjects: Μαθησιακός σχεδιασμός
Εξατομικευμένη μάθηση
Ψηφιακά εργαλεία συγγραφής
Εκπαιδευτικά σενάρια

description: Η παρούσα διπλωματική, εστιάζει στη θεώρηση της διδασκαλίας ως επιστήμης σχεδιασμού και του εκπαιδευτικού ως σχεδιαστή εποικοδομητικών και εξατομικευμένων εκπαιδευτικών σεναρίων. Παράλληλα, πραγματοποιήθηκε μία βιβλιογραφική ανασκόπηση για την εξατομικευμένη μάθηση, εστιάζοντας στην ταυτότητα, τις προκλήσεις και την ανάγκη υιοθέτησής της στην τυπική δευτεροβάθμια εκπαίδευση. Έχοντας περιγράψει την επίδραση της τεχνολογίας και την εξέλιξη της γνώσης του εκπαιδευτικού από τη γνώση περιεχομένου (CK) στην τεχνολογική, παιδαγωγική γνώση περιεχομένου (TPACK), μελετήθηκε η περίπτωση σχεδιασμού ενός σεναρίου ΤΠΕ με το ψηφιακό εργαλείο μαθησιακού σχεδιασμού WebCollage και ο μετασχηματισμός του σε σενάριο εξατομικευμένης μάθησης χρησιμοποιώντας το ψηφιακό εργαλείο CPELDS. Στο πλαίσιο της διπλωματικής πραγματοποιήθηκε σύγκριση των δύο εργαλείων ως προς τη διάσταση της αναπαράστασης και της υποστήριξης που προσφέρουν. Παράλληλα, αποτιμήθηκε η εμπειρία σχεδιασμού εκπαιδευτικού σεναρίου με αυτά ως προς την αξία τους για την εκπαιδευτική πράξη και την υποστήριξη του εκπαιδευτικού στο νέο ρόλο που αναλαμβάνει σε σύγχρονα εκπαιδευτικά πλαίσια που ενισχύονται από ψηφιακές τεχνολογίες.
The mass discrepancy acceleration relation in early-type galaxies: extended mass profiles and the phantom menace to MOND
Creators: name: Janz, Joachim
name: Cappellari, Michele
name: Romanowsky, Aaron J.
name: Ciotti, Luca
name: Alabi, Adebusola
name: Forbes, Duncan A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The dark matter (DM) haloes around spiral galaxies appear to conspire with their baryonic content: empirically, significant amounts of DM are inferred only below a universal characteristic acceleration scale. Moreover, the discrepancy between the baryonic and dynamical mass, which is usually interpreted as the presence of DM, follows a very tight mass discrepancy acceleration (MDA) relation. Its universality, and its tightness in spiral galaxies, poses a challenge for the DM interpretation and was used to argue in favour of MOdified Newtonian Dynamics (MOND). Here, we test whether or not this applies to early-type galaxies. We use the dynamical models of fast-rotator early-type galaxies by Cappellari et al. based on ATLAS$^{3D}$ and SLUGGS data, which was the first homogenous study of this kind, reaching ~4 $R_e$, where DM begins to dominate the total mass budget. We find the early-type galaxies to follow an MDA relation similar to spiral galaxies, but systematically offset. Also, while the slopes of the mass density profiles inferred from galaxy dynamics show consistency with those expected from their stellar content assuming MOND, some profiles of individual galaxies show discrepancies.
description: 7 pages, 3 figures, accepted for publication in MNRAS
Proceedings First Workshop on Causal Reasoning for Embedded and safety-critical Systems Technologies
Creators: name: Gössler, Gregor
name: Sokolsky, Oleg
Publisher: name: arXiv
Year: 2016
Subjects: subject: Logic in Computer Science (cs.LO)
subject: Artificial Intelligence (cs.AI)
subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: Formal approaches for automated causality analysis, fault localization, explanation of events, accountability and blaming have been proposed independently by several communities --- in particular, AI, concurrency, model-based diagnosis, formal methods. Work on these topics has significantly gained speed during the last years. The goals of CREST are to bring together and foster exchange between researchers from the different communities, and to present and discuss recent advances and new ideas in the field. The workshop program consisted of a set of invited and contributed presentations that illustrate different techniques for, and applications of, causality analysis and fault localization. The program was anchored by two keynote talks. The keynote by Hana Chockler (King's College) provided a broad perspective on the application of causal reasoning based on Halpern and Pearl's definitions of actual causality to a variety of application domains ranging from formal verification to legal reasoning. The keynote by Chao Wang (Virginia Tech) concentrated on constraint-based analysis techniques for debugging and verifying concurrent programs. Workshop papers deal with compositional causality analysis and a wide spectrum of application for causal reasoning, such as debugging of probabilistic models, accountability and responsibility, hazard analysis in practice based on Lewis' counterfactuals, and fault localization and repair.
A study of consolidation behaviour of clays by the velocity method
Creators: name: Wo., Patrick Lun Tak
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.