cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Enhanced high-order harmonic generation from periodic potentials in inhomogeneous laser fields
Creators: name: Du, Tao-Yuan
name: Guan, Zhong
name: Zhou, Xiao-Xin
name: Bian, Xue-Bin
Publisher: name: arXiv
Year: 2016
Subjects: subject: Optics (physics.optics)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We theoretically study high-order harmonic generation (HHG) from solid-phase systems in spatially inhomogeneous strong laser fields originated by resonant plasmons within a metallic nanostructure. The intensity of the second plateau in HHG may be enhanced by two-three orders and be comparable with the intensity of the first plateau. This is due to bigger transition probabilities to higher conduction bands. It provides us a practical way to increase the yields of HHG with laser intensity below the damage threshold. It presents a promising way to triple the range of HHG spectra in experimental measurements. It also allows to generate intense isolated attosecond pulse from solids driven by few-cycle laser fields.
Modelling of Thin Back Amorphous-Crystalline Si Heterojunction (BACH) PV
Creators: name: Chowdhury, Z.R.
name: Zukotynski, S.
name: Kherani, N.P.
Publisher: name: WIP
Year: 2011
Subjects: Wafer-based Silicon Solar Cells and Materials Technology
Silicon Solar Cell Characterisation and Modelling

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 1576-1580
description: High efficiency features of heterojunction silicon solar cells and back-contact homojunction solar cells
can be integrated in Back Amorphous-Crystalline silicon Heterojunction (BACH) solar cell. Use of only low
temperature fabrication processes allows this cell to be fabricated using thin wafers. This article presents a twodimensional
modeling study of the BACH cell concept. A parametric study of the BACH cell has been carried out
using Sentaurus after having benchmarked the simulation process. Solar cell efficiency of 24.4% is obtained for AM
1.5 global spectrum with VOC greater than 720 mV and JSC exceeding 40 mA/cm2, for practical cell parameters. An
optical model addressing photo generation accurately in thick and thin absorbers is presented.
Dynamic Mechanical Loads on PV-Modules
Creators: name: Aßmus, M.
name: Jack, S.
name: Köhl, M.
name: Weiss, K.-A.
Publisher: name: WIP-Munich
Year: 2009
Subjects: Components for PV Systems
PV Modules

description: 24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 3395-3397
description: Photovoltaic (PV)-modules are not only exposed to static mechanical loads, such as snow and wind
loads (for building integrated modules), as tested in the current standard IEC 61215. The highly dynamic loads occur
when wind triggers oscillations. It is obvious that the dynamic loads are more likely to cause fatigue of materials, especially
of PV-cells and connecting wires.
The dynamic behavior of modules with different designs and sizes is analyzed by different methods. Outdoor measurements
of the deflection show the dynamic behavior of different types of modules under wind loads and the correlation
between wind speed and deflection. Numerical calculations, based on FEM-modeling, showed that their resonance
frequencies are typically in the range from 1Hz to 100Hz, depending on the modes.
Results of the outdoor measurement and numerical simulations are reported.
Market economy and the emergence of social and gender inequality among Jakun Orang Asli
Creators: name: Vidal, Aude
Publisher: name: Zenodo
Year: 2024
Subjects: subject: Social anthropology

description: Despite Malaysia’s economic emergence, Orang Asli communities remain among the poorest in the country. Multiple factors are responsible for this situation and result in an important impact on their life. The Jakun village of Kampung Peta (Mersing, Johor) has been surveyed three times between the 1960s and 1999. The goal of my own study was to measure the effect of the development of a market economy on the village’s economic and social life. In 2019, at the time of my survey, the village of Kampung Peta is still benefiting from good material and social conditions: a pristine environment, a national park nearby offering the resources of tourism, and a strong collective leadership. Are these favourable conditions sufficient to shift securely from subsistence economy to market economy? In order to understand the economic opportunities, dreams and constraints of the Jakun of Kampung Peta, I surveyed the sources of income of the whole village and more precisely the incomes of fifteen households of various socio-economic status, based on their declarations during qualitative interviews. As formal employment and free-lance economic opportunities outside the primary sector are scarce and women have restricted access to them, my conclusions raise concern regarding the rise of social and gender inequality, as already observed in 1999.
Influence of Back Contact TCO Morphology on Silicon Thin Film Solar
Creators: name: Lai, K.-C.
name: Wang, J.-H.
name: Lu, C.-H.
name: Tsai, F.-J.
name: Yeh, C.-H.
name: Houng, M.-P.
Publisher: name: WIP-Munich
Year: 2010
Subjects: Thin Film Solar Cells
Amorphous and Microcrystalline Silicon Solar Cells

description: 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 2893-2895
description: This paper considers texturing of ZnO:Ga (GZO) films used as back contacts in amorphous silicon (a-
Si) thin film solar cells. GZO thin films are first prepared by conventional methods. The as-deposited GZO surface
properties are modified so that their use as back contacts on a-Si solar cells is enhanced. Texturing is performed by
simple dry plasma etching in a CVD process chamber, power=100W, substrate temperature=190Cº (temperature held
at 190Cº because thin film solar cells are damaged above 200Cº), pressure=400Pa, process gas H2 flow=700sccm.
Conventional a-Si solar cells are fabricated with and without GZO back contact surface treatment. Comparison of the
with/without texturing GZO films shows that plasma etching increases optical scattering reflectance and reflection
haze. SEM and TEM are used to evaluate the morphological treatment-induced changes in the films. Comparison of
the a-Si solar cells with/without texturing shows that the plasma treatment increases both the short-circuit current
density and fill factor. Consequently, a-Si solar cell efficiency is relatively improved by 4.6%.
Novel Contact Probes for Characterization of Crystalline Silicon Solar Cells with and without Bus Bars
Creators: name: Grischke, R.
name: Tarasenko, V.
name: Nebusov, V.
name: Bram Sadlik, B.
name: Rubin, L.
Publisher: name: WIP
Year: 2011
Subjects: Wafer-based Silicon Solar Cells and Materials Technology
Silicon Solar Cell Characterisation and Modelling

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 1558-1562
description: The current-voltage characterization (IV-curve) is the essential measurement method for power bin
classification used in industrial PV solar cell manufacturing. Measurement bars with spring loaded contact pins have
been established as reliable contact probes widely used for contacting wafer based silicon solar cells. These probes
work well on solar cells with H-pattern front metallization grids consisting of printed current collecting fingers which
lead into 2 or 3 printed bus bars. However, the Day4™ Energy technology has substituted the printed bus bars with
its unique electrode interconnection technology which consists of parallel alloy coated copper wires embedded in a
polymeric film. Conventional contact bars with a restricted number of spring loaded pin probes are not suitable for
contacting such bus bar less solar cells. Therefore, Day4™ Energy developed contact probes which form a reliable
contact to every finger in the solar cell simultaneously. In this work we will present different patented contacting
concepts suitable for contacting solar cells with or without printed bus bars. We demonstrate the accuracy,
repeatability, and durability of the novel measurement probes and demonstrate industrial feasibility by means of a
field test performed on a solar cell mass production line.
Micromorph Silicon Solar Cell Research and Development at NEXT ENERGY
Creators: name: Von Maydell, K.
name: Chakanga, K.
name: Sergeev, O.
name: Feser, C.
name: Rogler, D.
name: Stahr, F.
name: Geißendörfer, S.
name: Lacombe, J.
name: Siepmann, O.
name: Schumacher, B.
name: Klement, P.
name: Schäfer, C.
name: Vehse, M.
name: Sürig-Morieng, J.
name: Kellermann, M.
Publisher: name: WIP-Munich
Year: 2010
Subjects: Thin Film Solar Cells
Amorphous and Microcrystalline Silicon Solar Cells

description: 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 3032-3035
description: In this paper the activities of the photovoltaics group at the EWE research centre – NEXT ENERGY is
described. The focus of the work lies on thin film silicon solar cells. A baseline process has been implemented
allowing the deposition of state-of-the-art micromorph tandem solar cells. This is done with the goal to
substantionally increase the efficiency of this kind of cells in the future and to build up the base for new concepts like
triple junction solar cells. Detailed simulations were performed to get physical insight into the fundamental
mechanisms in the solar cell and to extract further potential of efficiency enhancement. 3-dimensional optical
simulations of structures with realistic topography will be presented. First experiments with ps-laser scribing have
been performed for TCO and a-Si:H ablation At the end an outlook about the triple junction activities will be given.
Prediction of Global Solar Radiation in Abu Dhabi City – UAE
Creators: name: Assi, A.
name: Al Shamisi, M.
name: Hejase, H.
Publisher: name: WIP
Year: 2011
Subjects: PV Systems
Large PV Power Plants and Distributed PV: System Aspects and Grid Connection

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 4328-4333
description: Measurements of air temperature, relative humidity, wind and sunshine duration between 1993 and
2008 for Abu Dhabi city in United Arab Emirates (UAE) were used for the estimation of monthly average global
solar radiation (GSR) in the city of Abu Dhabi. Neural network and Time-series regression techniques were used in
this work. Weather data between 1993 and 2003 were used for training the neural network, while the data of selected
years from 2004 to 2008 were used for validation. Obtained results show outperformance of ANN models compared
to those developed with regression model.
Innovated Workplace for Measuring Photoluminiscence at Very Low Temperature
Creators: name: Vesely, A.
name: Vanek, J.
name: Stojan, R.
name: Dolensky, J.
name: Barinka, R.
Publisher: name: WIP
Year: 2011
Subjects: Wafer-based Silicon Solar Cells and Materials Technology
Silicon Solar Cell Characterisation and Modelling

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 1512-1515
description: This paper deals with the modern diagnostic methods of defects detection of solar cells. Defects are
detected by electroluminescence and photoluminescence methods. The main focus of this work is an innovation
workplace for measuring solar cell defects at very low temperatures using photoluminescence. Liquid nitrogen is
used to cooling solar cells. By using low temperatures can be detection methods to obtain more objective results of
diagnostic defects.
Near-infrared spectro-interferometry of Mira variables and comparisons to 1D dynamic model atmospheres and 3D convection simulations
Creators: name: Wittkowski, M.
name: Chiavassa, A.
name: Freytag, B.
name: Scholz, M.
name: Hoefner, S.
name: Karovicova, I.
name: Whitelock, P. A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We obtained a total of 20 near-infrared K-band spectro-interferometric snapshot observations of the Mira variables o Cet, R Leo, R Aqr, X Hya, W Vel, and R Cnc with a spectral resolution of about 1500. We compared observed flux and visibility spectra with predictions by CODEX 1D dynamic model atmospheres and with azimuthally averaged intensities based on CO5BOLD 3D dynamic model atmospheres including convection. Our visibility data confirm the presence of spatially extended molecular atmospheres located above the continuum radii with large-scale inhomogeneities or clumps that contribute a few percent of the total flux. The detailed structure of the inhomogeneities or clumps show a variability on time scales of 3 months and above. Both modeling attempts provided satisfactory fits to our data. In particular, they are both consistent with the observed decrease in the visibility function at molecular bands of water vapor and CO, indicating a spatially extended molecular atmosphere. Observational variability phases are mostly consistent with those of the best-fit CODEX models, except for near-maximum phases, where data are better described by near-minimum models. Rosseland angular diameters derived from the model fits are broadly consistent between those based on the 1D and the 3D models and with earlier observations. We derived fundamental parameters including absolute radii, effective temperatures, and luminosities for our sources. Our results provide a first observational support for theoretical results that shocks induced by convection and pulsation in the 3D CO5BOLD models of AGB stars are roughly spherically expanding and of similar nature to those of self-excited pulsations in 1D CODEX models. Unlike for red supergiants, the pulsation- and shock-induced dynamics can levitate the molecular atmospheres of Mira variables to extensions that are consistent with observations.
description: Accepted for publication in A&A. 16 pages, 10 figures
Function & Efficiency Test for Large Scale PV Power Plants
Creators: name: Dittrich, J.
name: Litzenburger, B.
name: Hupach, U.
name: Bauerdick, C.
Publisher: name: WIP
Year: 2011
Subjects: PV Systems
Large PV Power Plants and Distributed PV: System Aspects and Grid Connection

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 4283-4289
description: Large scale PV power plants have been one driver for the strong growth of installed PV capacity in
the last years. Those large plants require significant financial investments and therefore the owner is aiming for
highest quality of his solar farm which in his terms means yield and reliability leading to a high annual energy
production. As a part of a quality assurance procedure, a measurement method during the commissioning of PV
power plants is presented in this paper. In order to really demonstrate the power capacity of the power plant,
methodology and measurement set up to derive STC power from actual power measurements have been
developed. Power blocks up to 2 MW can be tested at a time. The method bases on a proposal from the Spanish
IES solar research institute but has been modified for the requirements of the commercial power plant business.
Test laboratories responsible for calibration standards for measurement equipment and PV reference devices are
in accordance with ISO/IEC 17025.
Constraints on the flavor-dependent non-standard interaction in propagation from atmospheric neutrinos
Creators: name: Yasuda, Osamu
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The sensitivity of the atmospheric neutrino experiments to the non-standard flavor-dependent interaction in neutrino propagation is studied under the assumption that the only nonvanishing components of the non-standard matter effect are the electron and tau neutrino components $ε_{ee}$, $ε_{eτ}$, $ε_{ττ}$ and that the tau-tau component satisfies the constraint $ε_{ττ}=|ε_{eτ}|^2/(1+ε_{ee})$ which is suggested from the high energy behavior for atmospheric neutrino data.
description: 5 pages, 8 figures, uses jpconf.cls. Contribution for the proceedings of the TAUP2015, International Conference on Topics in Astroparticle and Underground Physics, 7-11 September 2015, Torino, Italy
Variation of Spectral and Timing Properties in the Extended Burst Tails from the Magnetar 4U 0142+61
Creators: name: Chakraborty, Manoneeta
name: Göğüş, Ersin
name: Muş, Sinem Şaşmaz
name: Kaneko, Yuki
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Extended emission episodes with intensity above the pre-burst level are observed following magnetar bursts from a number of soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs). Such extended tail emission were observed subsequent to two events detected from AXP 4U 0142+61. We investigated in detail the evolution of spectral and temporal properties during these two tail segments using RXTE/PCA observations, and report distinct variations both in the spectral and temporal behavior throughout the tails. In particular, sudden enhancement of pulsation amplitude in conjunction with bursts, and smooth decline of X-ray emission (cooling) during the tail were observed in both cases. We suggest that an inefficiently radiating trapped fireball formed during the burst, which can heat up the stellar surface, is able to explain the tail properties and its energetics. We also present the episodic detection of absorption and emission features during tails. One possible mechanism that has been proposed to give rise to such spectral lines is the proton/ion cyclotron resonance process which has been suggested to offer a valuable tool in probing the complex magnetic field of magnetars.
description: 14 pages, 9 figures, 3 tables, accepted for publication in ApJ
From Student to Coach: The Dynamic Nature of Professional Learning and Identity Development of BSc Sports Coaching Students
Creators: name: Fonseca, Joana
Publisher: name: Cardiff Metropolitan University
Year: 2022
Subjects: Sport and exercise psychology

description: During recent years, Portugal has witnessed an increase in the provision of sports coaching programmes (DGES, 2019). The foundation of such a development has been the recognition of academic degrees as a qualified route for coach certification (IDP, 2010). Yet, despite such progress, little remains known about the actuality of the learning experience in those environments, and the impact of those experiences on the development of student-coaches ‘knowledgeable’ working identities (Wenger-Trayner & Wenger-Trayner, 2015). Consequently, in spite of the growing recognition that coaches’ education requires a better understanding of social, cultural and historical factors (e.g., Townsend & Cushion, 2015; Jones, Morgan & Harris, 2012), the influence of such features on personal ideologies, regimes of competence and practices exhibited by neophyte coaches remain largely unexplored.
In response, the current study attempts to map the intellectual and social development of 16 undergraduate sports coaching students by examining how their knowledge construction and sense of self is shaped, reproduced, manifested and transformed, over the length of their 3 years undergraduate degree. Following an interpretivist paradigm, the research design used a mixture of focus group interviews, video diaries and written reflections to explore the students’ on-going experiences of change throughout their learning journey. The data were subsequently examined using inductive analysis inspired by Charmaz’s (2006) interpretations of grounded theory. The main results demonstrated that the students’ learning, as opposed to being a cognitive content-driven process, was predominantly social and relational in character; it being influenced by perceived authority sources and the external validation of knowledge. Simultaneously, the students’ professional (i.e., coach) identity development was directly linked to the academic curriculum and the staff who delivered it. Here, the contradictory and ambiguous environment of content and teaching approaches pushed the students to adopt more strategic and reflective positions as learners.
Such findings come with a realisation that knowledge is relative and, therefore, making individual commitment and argumentative ownership is essential for coach identity creation and development. Overall, the study suggests the need to create learning environments that instigate an acceptance of ambiguity and stimulates a constant reflection on personal identities for the development of insightful coaches.
Effects of CO2 Introduction to the Reactive RF Sputtering Process for Micro-Crystalline Ge Thin Films
Creators: name: Hatano, Y.
name: Kataoka, T.
name: Isomura, M.
Publisher: name: WIP-Munich
Year: 2010
Subjects: Thin Film Solar Cells
Amorphous and Microcrystalline Silicon Solar Cells

description: 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 3000-3002
description: We proposed microcrystalline germanium (μc-Ge) as a material for infrared-sensitive photovoltaic cells.
The μc-Ge usually shows no photo-sensitivity became of the strong p-type conduction due to negatively changed
grain boundary defects. To suppress the p-type conduction, the compensation was attempted by oxygen doping. The
oxygen doping was done by introducing carbon dioxide (CO2) and oxygen (O2) gases in the reactive sputtering
process. We successfully obtained photo-sensitive μc-Ge with high crystallinity for the first time, due to the both CO2
and O2 introduction. The highest photo-sensitivity of 2.0 times was achieved by introducing 1.0×10-3 ccm of CO2
into the sputtering gas (Ar:10ccm, H2:100ccm). The crystallinity of μc-Ge is more affected by the introduction of
CO2 than O2. The results show that the p-type defects in μc-Ge films can be compensated by the oxygen doping. The
μc-Ge films with small amount of oxygen is a good candidate of narrow gap materials for photovoltaic cells and other
devices with sensitivity of infrared light.
Estimation of the lifetime of small helium bubbles near tungsten surfaces -- a methodological study
Creators: name: Cui, Jiechao
name: Wu, Zhangwen
name: Hou, Qing
Publisher: name: arXiv
Year: 2016
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Under low energy and high flux/fluence irradiation of helium (He) atoms, the formation and bursting of He bubbles on tungsten (W) surfaces play important roles in the morphological evolution of component surfaces and impurity production in fusion reactors. Microscopically, the bursting of He bubbles is a stochastic process, and He bubbles have statistically average lifetimes. In the present paper, a molecular dynamics-based method was developed to extract, for the first time, the lifetime of He bubbles near tungsten surfaces. It was found that He bubble bursting can be treated as an activated event. Its occurrence frequency or, equivalently, the average lifetime of bubbles follows the Arrhenius equation. For a given bubble size, the activation energy exhibits a good linear dependence with the depth, and the pre-exponential factor obeys the Meyer-Nedle rule. These results are useful for establishing a model in multi-scale simulations of impurity production in the fusion plasma and of the morphological evolution of component surfaces.
Series Resistance Imaging for Optimization of the Firing Process for Screen Printed Silicon Solar Cells
Creators: name: Angelskår, H.
name: Nordseth, O.
name: Olaisen, B.R.
name: Popovici, N.
name: Stensrud Marstein, E.S.
Publisher: name: WIP
Year: 2011
Subjects: Wafer-based Silicon Solar Cells and Materials Technology
Silicon Solar Cell Characterisation and Modelling

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 1520-1523
description: A luminescence based series resistance imaging method was used for the optimization of the firing
process for screen printed silicon solar cells. The firing temperature and power settings of the individual infrared
lamps in the belt furnace were controlled to establish a homogeneous series resistance over the cell area. In addition,
the series resistance images were used to compare the front side contact interface in areas of high and low series
resistance with cross-sectional scanning electron microscope images. This study illustrates an optimization procedure
for firing of screen printed solar cells, and also the usefulness of spatially resolved information such as that obtained
from photoluminescence based series resistance imaging.
Radical Decarboxylation for the Synthesis of Functionalised Polymers
Creators: name: AYURINI, MERI
Publisher: name: Monash University
Year: 2023
Subjects: Organic chemical synthesis
Macromolecular materials
Polymerisation mechanisms

description: Controlled radical polymerisations have emerged as powerful approaches in preparing polymers with predetermined molecular weights and low dispersities. Likewise, the ability to functionalise polymer endgroups has been a significant development in polymer synthesis since it permits the production of versatile polymer materials containing dyes, drugs, biomolecules or other conjugates. This thesis reports novel methods to prepare the functionalised polymers in a single-step synthesis employing commercially available carboxylic acids through radical decarboxylation. These developed methods are suitable to a broad range of carboxylic acid based materials, leading to polymers with various alpha endgroup derived from the carboxylic acids.
RISK MANAGEMENT IN SADC'S CROSS-BORDER SUPPLY CHAINS
Creators: name: Mbonigaba Celestin*, A. Dinesh Kumar** & M. Vasuki***
Publisher: name: Zenodo
Year: 2024

description: The study on "Risk Management in SADC’s Cross-Border Supply Chains" provides an in-depth analysis of the challenges and strategies associated with managing risks in the Southern African Development Community (SADC) region. The research focuses on the volatile sectors of energy and commodities, examining how these industries are particularly susceptible to disruptions due to political instability, regulatory changes, infrastructure deficiencies, and environmental factors. The study highlights the significant economic role that cross-border supply chains play in the region, contributing to about 25% of total trade within SADC. However, these supply chains face numerous risks, including transportation disruptions, currency fluctuations, and natural disasters, which have been exacerbated by events such as the COVID-19 pandemic and political unrest in member states.

Traditional risk management approaches, such as insurance and contingency planning, are being supplemented by innovative techniques, including predictive analytics and block chain technology, to improve resilience. The study also emphasizes the importance of regional collaboration, technological investment, and capacity building as critical strategies for mitigating risks. It recommends the harmonization of regulatory frameworks, the establishment of regional risk management task forces, and the adoption of digital customs platforms to streamline processes and reduce delays. Furthermore, the research calls for the creation of specialized training programs to address the expertise deficit in risk management across the region. By adopting these strategies, SADC can enhance the stability and efficiency of its cross-border supply chains, ultimately contributing to regional economic growth and development.
Analysis of a-SiNx:H Passivated Si Surfaces Based on Injection Level Dependent Lifetime and Capacitance/Conductance-Voltage Measurements
Creators: name: Haug, H.
name: Helland, S.
name: Nordseth, O.
name: Monakhov, E.V.
name: Stensrud Marstein, E.S.
Publisher: name: WIP
Year: 2011
Subjects: Wafer-based Silicon Solar Cells and Materials Technology
Silicon Solar Cell Characterisation and Modelling

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 1524-1529
description: In this paper, injection level dependent measurements of the effective surface recombination velocity (SRV) at silicon
surfaces passivated with plasma-enhanced chemical vapor deposited silicon nitride films have been performed using
the quasi-steady state photoconductance method. Values for the interface state density and fixed insulator charge
have been extracted both by fitting the injection level dependent SRV data to an extended Shockley-Read Hall model
and from direct measurements of capacitance- and conductance vs. voltage characteristics on Al/a-SiNx:H/Si
structures. The relation between these microstructural parameters and the stoichiometry of the a-SiNx:H layers was
determined by analyzing a series of samples produced by changing the gas flow ratio during deposition. The density
of interface states was found to decrease with increasing Si-content in the layers, an effect that may be attributed to
increased hydrogen content in the samples, causing an enhanced chemical passivation of dangling bonds. The fixed
charge density also decreases for the more Si-rich samples, but the values are still sufficiently high to keep inversion
conditions at the surface, resulting in a total lowering of the SRV with increasing Si-content. A lowering of both the
interface trap density and the SRV was observed after firing for all samples.
The Nature of H$β+$[O{\sc iii}] and [O{\sc ii}] emitters to $z \sim 5$ with HiZELS: stellar mass functions and the evolution of EWs
Creators: name: Khostovan, Ali Ahmad
name: Sobral, David
name: Mobasher, Bahram
name: Smail, Ian
name: Darvish, Behnam
name: Nayyeri, Hooshang
name: Hemmati, Shoubaneh
name: Stott, John P.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We investigate the properties of $\sim7000$ narrow-band selected galaxies with strong H$β+$[OIII] and [OII] nebular emission lines from the High-$z$ Emission Line Survey (HiZELS) between $z \sim 0.8 - 5.0$. Our sample covers a wide range in stellar mass ($M\sim10^{7.5 - 12.0}$ M$_\odot$), rest-frame equivalent widths (EW$_\mathrm{rest}\sim 10 - 10^5$ Å), and line luminosities ($L\sim10^{40.5 - 43.2}$ erg s$^{-1}$). We measure the H$β+$[OIII] and [OII]-selected stellar mass functions out to $z \sim 3.5$ and find that both $M_\star$ and $ϕ_\star$ increases with cosmic time, which may be due to the [OIII] selection including an increasing fraction of AGN at lower redshifts. The [OII]-selected stellar mass functions show a constant $M_\star\sim10^{11.6}$ M$_\odot$ and a strong, increasing evolution with cosmic time in $ϕ_\star$ in line with H$α$ studies. We also investigate the EW$_\mathrm{rest}$ evolution as a function of redshift with a fixed mass range (10$^{9.5 - 10.0}$ M$_\odot$) and find an increasing trend best represented by $(1+z)^{3.81\pm0.14}$ and $(1+z)^{2.72\pm0.19}$ up to $z\sim 2$ and $\sim 3$ for H$β$+[OIII] and [OII] emitters, respectively. This is the first time that the EW evolution has been directly measured for H$β+$[OIII] and [OII] emitters up to these redshifts. There is evidence for a slower evolution for $z > 2$ in the H$β+$[OIII] EW and a decreasing trend for $z > 3$ in the [OII] EW evolution, which would imply low [OII] EW at the highest redshifts and higher [OIII]/[OII] line ratios. This suggests that the ionization parameter at higher redshift may be significantly higher than the local Universe. Our results set the stage for future near-IR space-based spectroscopic surveys to test our extrapolated predictions and also produce $z > 5$ measurements to constrain the high-$z$ end of the EW$_\mathrm{rest}$ and [OIII]/[OII] evolution.
description: 20 pages, 10 figures, 6 tables, submitted to MNRAS
Modeling the microstructural evolution during constrained sintering
Creators: name: Bjørk, R.
name: Frandsen, H. L.
name: Pryds, N.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A numerical model able to simulate solid-state constrained sintering is presented. The model couples an existing kinetic Monte Carlo (kMC) model for free sintering with a finite element model (FEM) for calculating stresses on a microstructural level. The microstructural response to the local stress as well as the FEM calculation of the stress field from the microstructural evolution is discussed. The sintering behavior of a sample constrained by a rigid substrate is simulated. The constrained sintering results in a larger number of pores near the substrate, as well as anisotropic sintering shrinkage, with significantly enhanced strain in the central upper part of the sample surface, and minimal strain at the edges near the substrate. All these features have also previously been observed experimentally.
description: 9 pages, 7 figures
In-Line Quantum Efficiency Measurement for I-V Spectral Mismatch Correction
Creators: name: Lee, J.
name: Lin, M.J.
name: Su, P.P.
name: Wang, F.
Publisher: name: WIP
Year: 2011
Subjects: Wafer-based Silicon Solar Cells and Materials Technology
Silicon Solar Cell Characterisation and Modelling

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 1409-1412
description: The most important PV device efficiency and power can be measured by Solar Simulator/I-V
testing system. However, even solar simulator meets Class A (IEC-60904 -9) spectral match classification
requirement against AM1.5G standard spectrum (IEC-60904-3), the spectral mismatch error is still one of the
major sources of inaccuracy for Isc, Pmp & Eff measurement. It is well known that this error can be corrected by
calculating mismatch factor (MF) with known optical spectral distribution of the solar simulator used and spectral
response characteristics of reference PV device and test device. But, it is impractical to conduct MF correction for
In-line production application because the time consuming for quantum efficiency test (used to derive spectral
response) to each individual PV device under test. This work proposes an innovative solution by incorporating
multiple wavelength LEDs and CDMA (Code Division Multiple Access) modulation and demodulation technique
to drastically reduce the time required for quantum efficiency measurement down to less than 1 second.
Consistency of multi-time Dirac equations with general interaction potentials
Creators: name: Deckert, Dirk-André
name: Nickel, Lukas
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: In 1932, Dirac proposed a formulation in terms of multi-time wave functions as candidate for relativistic many-particle quantum mechanics. A well-known consistency condition that is necessary for existence of solutions strongly restricts the possible interaction types between the particles. It was conjectured by Petrat and Tumulka that interactions described by multiplication operators are generally excluded by this condition, and they gave a proof of this claim for potentials without spin-coupling. Under smoothness assumptions of possible solutions we show that there are potentials which are admissible, give an explicit example, however, show that none of them fulfills the physically desirable Poincaré invariance. We conclude that in this sense Dirac's multi-time formalism does not allow to model interaction by multiplication operators, and briefly point out several promising approaches to interacting models one can instead pursue.
Homogeneity of Screen Printed Metallization Lines and Relevance for Solar Cell Efficiency
Creators: name: Rommel, S.
name: Einsele, F.
name: Guo, H.
name: Ametowobla, M.F.
name: Manz, D.
Publisher: name: WIP
Year: 2011
Subjects: Wafer-based Silicon Solar Cells and Materials Technology
Silicon Solar Cell Characterisation and Modelling

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 1538-1541
description: We investigate the performance of screen printed metallization lines and their influence on cell efficiency. Weighting
coefficients for printed line width and resistance allow to estimate the losses in solar cell output power. From a simple
geometrical model of line homogeneity, the line resistance is calculated for inhomogeneous lines. By comparing
homogeneous and inhomogeneous lines we calculate the yield of silver consumption.
Timing the evolution of quiescent and star-forming local galaxies
Creators: name: Pacifici, Camilla
name: Oh, Sree
name: Oh, Kyuseok
name: Lee, Jaehyun
name: Yi, Sukyoung K.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Constraining the star formation histories (SFHs) of individual galaxies is crucial to understanding the mechanisms that regulate their evolution. Here, we combine multi-wavelength (ultraviolet, optical, and infrared) measurements of a very large sample of galaxies (~230,000) at z<0.16, with physically motivated models of galaxy spectral energy distributions to extract constraints on galaxy physical parameters (such as stellar mass and star formation rate) as well as individual SFHs. In particular, we set constraints on the timescales in which galaxies form a certain percentage of their total stellar mass (namely, 10, 50 and 90%). The large statistics allows us to average such measurements over different populations of galaxies (quiescent and star-forming) and in narrow ranges of stellar mass. As in the downsizing scenario, we confirm that low-mass galaxies have more extended SFHs than high-mass galaxies. We also find that at the same observed stellar mass, galaxies that are now quiescent evolve more rapidly than galaxies that are currently still forming stars. This suggests that stellar mass is not the only driver of galaxy evolution, but plays along with other factors such as merger events and other environmental effects.
description: 12 pages, 9 figures, accepted for publication in ApJ
Lithium doped graphene as spintronic devices
Creators: name: Kheirabadi, Narjes
Publisher: name: arXiv
Year: 2015
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Generating spintronic devices has been a goal for the nano-science. We have used density function theory to determine magnetic phases of single layer and bilayer lithium doped graphene nanoflakes. We have introduced graphene flakes as single molecular magnets, spin on/off switches and spintronic memory devices. To aim this goal, adsorption energies, spin polarizations, electronic gaps, magnetic properties and robustness of spin-polarized states have been studied in the presence of dopants and second layers. We find that for bilayer SMMs with two layers of different sizes the highest occupied molecular orbital and the lowest unoccupied molecular orbital switch between the layers. Based on this switch of molecular orbitals in a bilayer graphene SMM, spin on/off switches and spintronic memory devices could be achievable.
Tuning the Rear Side Morphology of Crystalline Silicon Solar Cells by Plasma Chemical Etching at Atmospheric Pressure for Maximal Light Trapping Effect
Creators: name: Poruba, A.
name: Šenkýr, J.
name: Cech, P.
name: Wostry, P.
name: Barinkova, P.
name: Barinka, R.
name: Purkrt, A.
name: Vanecek, M.
name: Lopez, E.
name: Mäder, G.
name: Dresler, B.
name: Dani, I.
name: Franta, D.
name: Necas, D.
Publisher: name: WIP
Year: 2011
Subjects: Wafer-based Silicon Solar Cells and Materials Technology
Silicon Solar Cell Characterisation and Modelling

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 1542-1546
description: Optical properties of textured monocrystalline silicon substrates after single side atmospheric pressure
plasma chemical etching (APPCE) were studied in dependence on the treatment conditions in the SF6-O2 gas mixture.
This treatment leads to the surface morphology modification, namely to the controlled change of top angles of
random pyramids from original 70.5° to resulting 90-150°. Influence of the one side morphology modification of
silicon wafers on the resulting optical spectra was calculated by Monte Carlo modeling as well as it was measured by
combined T/R characterization. The same modeling approach has been applied to predict the light trapping behavior
of solar cell structures with dielectric passivation of the rear side which confirms the increase of the internal
reflectivity of c-Si solar cell structure from values of about 65-70% for standard screen-printed Al to well over 90%.
Rear side morphology modification (by two various APPCE methods) was applied for the set of c-Si solar cells with
Al screen-printed back contact. This process (replacing also the edge isolation step) leads to slight performance
increase compared to standard solar cell structure.
The Sol-Ion System: Prototype Deployment in French Overseas and Southern German Field Trial Locations and Logged Parameters for PV Storage System at Home Locations
Creators: name: Binder, J.
name: Marcel, J.-C.
name: Schmiegel, A.U.
name: Thomas, U.
name: Martin, N.
name: Jehoulet, C.
name: Landau, M.
name: Mohring, H.-D.
Publisher: name: WIP
Year: 2011
Subjects: PV Systems
Large PV Power Plants and Distributed PV: System Aspects and Grid Connection

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 4201-4204
description: Solar home systems combining PV and storage capacity through Lithium-Ion batteries have been
developed within the French-German Sol-ion project. Deployment into a field trial with 25 installations in French
Overseas, 20 installations in Southern Germany and several research institutes has commenced, allowing for the test
of different operation modes, including back-up for grid failure, optimization of self-consumption and grid support.
Details of the types of installations, the operation modes and parameters collected in the field trial are given including
first samples of collected data.
Voltage stress minimization by optimal reactive power control
Creators: name: Todescato, Marco
name: Simpson-Porco, John W.
name: Dörfler, Florian
name: Carli, Ruggero
name: Bullo, Francesco
Publisher: name: arXiv
Year: 2016
Subjects: subject: Optimization and Control (math.OC)
subject: Systems and Control (eess.SY)
subject: FOS: Mathematics
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: A standard operational requirement in power systems is that the voltage magnitudes lie within prespecified bounds. Conventional engineering wisdom suggests that such a tightly-regulated profile, imposed for system design purposes and good operation of the network, should also guarantee a secure system, operating far from static bifurcation instabilities such as voltage collapse. In general however, these two objectives are distinct and must be separately enforced. We formulate an optimization problem which maximizes the distance to voltage collapse through injections of reactive power, subject to power flow and operational voltage constraints. By exploiting a linear approximation of the power flow equations we arrive at a convex reformulation which can be efficiently solved for the optimal injections. We also address the planning problem of allocating the resources by recasting our problem in a sparsity-promoting framework that allows us to choose a desired trade-off between optimality of injections and the number of required actuators. Finally, we present a distributed algorithm to solve the optimization problem, showing that it can be implemented on-line as a feedback controller. We illustrate the performance of our results with the IEEE30 bus network.
description: 10 pages, 9 figures
The lifetime cost of a magnetic refrigerator
Creators: name: Bjørk, R.
name: Bahl, C. R. H.
name: Nielsen, K. K.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: The total cost of a 25 W average load magnetic refrigerator using commercial grade Gd is calculated using a numerical model. The price of magnetocaloric material, magnet material and cost of operation are considered, and all influence the total cost. The lowest combined total cost with a device lifetime of 15 years is found to be in the range \$150-\$400 depending on the price of the magnetocaloric and magnet material. The cost of the magnet is largest, followed closely by the cost of operation, while the cost of the magnetocaloric material is almost negligible. For the lowest cost device, the optimal magnetic field is about 1.4 T, the particle size is 0.23 mm, the length of the regenerator is 40-50 mm and the utilization is about 0.2, for all device lifetimes and material and magnet prices, while the operating frequency vary as function of device lifetime. The considered performance characteristics are based on the performance of a conventional A$^{+++}$ refrigeration unit. In a rough life time cost comparison between the magnetic refrigeration device and such a unit we find similar costs, the former being slightly cheaper, assuming the cost of the magnet can be recuperated at end of life.
description: 17 pages, 17 figures
Comparison of the Mono and Multicrystalline Performance of Multi-MW PV Grid-Connected Facilities in the Canary Islands (Spain) during Saharan Air Mass Invasion: Test Bench for Northern Africa
Creators: name: Montes, C.
name: González-Diaz, B.
name: Linares, A.
name: Llarena, E.
name: González, O.
name: Molina, D.
name: Pío, A.
name: Friend, M.
name: Cendagorta, M.
Publisher: name: WIP
Year: 2011
Subjects: PV Systems
Large PV Power Plants and Distributed PV: System Aspects and Grid Connection

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 4293-4296
description: The Canary Islands are a Spanish archipelago in the Atlantic Ocean, off the northwest coast of Africa,
about 100 km west of Morocco and Western Sahara. Due to the trade winds, northeast winds blowing almost
constantly, providing moisture after travelling hundreds of kilometres in contact with the sea, and due to the location
in almost tropical latitudes, the climate of the Canary Islands is mild, with warm and sunny summers and moderately
warm winters.
Due to their proximity to the Sahara desert, the Canary Islands are sometimes visited by dust clouds from the Sahara
desert. These clouds are caused by dust storms that are powered by strong winds in the Sahara and then these clouds
are driven over the Canary Islands by the easterly winds. These winds drag fine sand particles, causing the air to
become dense, reducing the visibility and increasing the temperature.
The Institute of Technology and Renewable Energies (ITER) has been installing several mono and multicristal silicon
photovoltaic plants in the island of Tenerife, in the Canary Islands, with a total power of about 40 MW. ITER also
carries out the operation and maintenance works for these photovoltaic installations.
The analysis of this phenomenon and its impact on photovoltaic solar energy production based on the used
technology in conditions similar to those of Northern Africa makes the Canary Islands a good test bench for this type
of facilities, which are also affected by invasions of air masses from the Sahara.