cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
In situ TEM investigation on the beam-driven mechanisms of Ag/Au nanoparticles at room temperature
Creators: name: Li, Xiaoru
Publisher: name: Imperial College London
Year: 2022

description: Over the last few decades, there have been significant developments in the field of nanotechnology from theoretical prediction to industrial application. Nanofabrication or nanomanufacturing has become a hot area in the past few decades due to the rapid development of electronics which requires the improvement of extremely small-scale manufacturing techniques. A chip-used field-effect transistor (FET) has been produced with a minimum size of about 5 nm via a photolithography method. However, as a top-down manufacturing method, photolithography is indirectly accompanied by the waste of resources, environmental pollution, and difficulty in recycling. There is a need to develop a more direct bottom-up technique at the nanoscale similar to macro-scale printing and additive manufacturing (AM). Improving characterization techniques provides an opportunity to observe events happening at the nanoscale. With increasing research in nano-experiments, many studies have recognized the difficulty of finding a satisfactory agreement between classical theory and results for small-sized nanoparticles (NPs). This requires a better understanding of the intrinsic mechanisms and inter-particle reactions between and among nanoparticles. It has been found that an electron beam can be utilized to induce the coalescence of NPs and directly control the movement of nanoclusters in the liquid reservoir in a TEM. Such expositions are unsatisfactory because NPs were performed in a liquid, and it is hard to clarify whether the findings were caused by the surrounding liquid phase or affected by the fundamental mechanisms of NPs themselves. In this study, we observed beam-driven events of solid-state NPs to remove any possible effect of liquid, capping agents, and ligands, for a better understanding of the intrinsic mechanisms of NPs. A systematic study of how the nano-deposition system contributes to the generation of NPs is still lacking. The nanoparticles' nucleation, growth, and deposition will be discussed in the work for obtaining size-controlled NPs. NPs (up to 15 nm in diameter) will be investigated via TEM for a better understanding of the intrinsic mechanisms of solid-state small-sized NPs. In-depth studies will be carried out focusing on beam-driven events of NPs, such as coalescence, Ostwald ripening, evaporation-condensation, and wetting. Moreover, the lattice reconstruction, shape evolution, and neck growth of NPs during coalescence will be also studied in situ in a TEM. These studies confirmed the possibility of using an electron beam to directly control the particle movement and realign the crystal of the nanostructure. The beam-driven coalescence of NPs will potentially benefit self-assembly and nanofabrication in the future, and in this work, nanocubes and nanorods were successfully created using beam manipulation.
Supplementary Material_PRV-00009-2022R1.pdf
Creators: name: Freeman, Spencer A.
name: Grinstein, Sergio
name: Orlowski, John
Publisher: name: figshare
Year: 2022
Subjects: subject: Physiology
subject: FOS: Biological sciences

description: Supplementary Material (Table S1-S3) for article entitled "Determinants, Maintenance and Function of Organellar pH" by S. A. Freeman, S. Grinstein and J. Orlowski published in Physiological Reviews
title: Mark Fenemore, Dismembered Policing in Postwar Berlin: The Limits of Four-Power Government
Creators: name: Teworte, Emma
Publisher: name: Max Weber Stiftung
Year: 2024
Subjects: subject: 9

description: German Historical Institute London Bulletin, vol. 46, no. 2GHI London Bulletin 2024, Bd. 46, Nr. 2, p. 107
Military Organization, Structure and Performance among the Karrayyu Oromo
Creators: name: Kumsa, Ginbar Negera
Publisher: name: Ethiopian Journal of Science and Sustainable Development
Year: 2023

description: The Karrayyu have been varyingly portrayed as people wandering to confront others or who lived in conflict hotspots and were sympathetic to military violence. Other scholars who have showed positive compassion to the Karrayyu have not dared to tell us how their military performance scaffolds their exit strategy from violent conflict and for maintaining them resilience. The Karrayyu maintain their views the conflict in the valley land largely emanated from the Karrayyu’s opposition against repressive multilayered actors who are assaulting them, confiscating their lands, and raiding their livestock. Among other issues, this study aims to reveal the Karrayyu military organization, structure, and performance succumbing to the gadaa system and what this will contribute to understanding them in humanity. The study was conducted by undertaking a historical research approach of analytical narrative and descriptive protocols. The study findings indicate that Karrayyu have formulated their military systems shaped by their local contexts and martial principles, codes, and taboos observed for all humans embedded in the egalitarian Gadaa system. Results of the study also indicate that, beyond the pastoralists’ stereotypic imaginary representations, the Karrayyu practice of military performance is an agency for mitigating circumstances and intermediate their resiliencies for maintaining survival. The researcher recommends such a study on the Karrayyu vantage point will contribute to bridging the existing gap and address prevailing flaws in the area.
description: Ethiopian Journal of Science and Sustainable Development, Vol 10 No 2 (2023): EJSSD
Nuclear and electromagnetic cascades induced by ultrahigh-energy cosmic rays in radio galaxies: implications for Centaurus A
Creators: name: Zhang, B. Theodore
name: Murase, Kohta
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Very-high-energy (VHE) $γ$-rays ($\gtrsim 0.1\rm~TeV$) and neutrinos are crucial for identifying accelerators of ultrahigh-energy cosmic rays (UHECRs), but this is challenging especially for UHECR nuclei. In this work, we develop a numerical code to solve the transport equation for UHECRs and their secondaries, where both nuclear and electromagnetic cascades are taken into account self-consistently, considering steady UHECR accelerators such as radio galaxies. In particular, we focus on Centaurus A, which has been proposed as one of the most promising UHECR sources in the local universe. Motivated by observations of extended VHE $γ$-ray emission from its kiloparsec-scale jet by the H.E.S.S. telescope, we study interactions between UHECRs accelerated in the large-scale jet and various target photon fields including blazar-like beamed core emission, and present a quantitative study on VHE $γ$-ray signatures of UHECR nuclei, including the photodisintegration and Bethe-Heitler pair-production processes. We show that VHE $γ$-rays from UHECR nuclei could be detected by the ground-based $γ$-ray telescopes given that the dominant composition of UHECRs consists of intermediate-mass (such as oxygen) nuclei
description: 14 pages, 4 figures, accepted for publication in MNRAS
Evanescent Wave Boundary Layers in Metamaterials and Sidestepping them through a Variational Approach
Creators: name: Srivastava, Ankit
name: Willis, John R.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: All metamaterial applications are based upon the idea that extreme material properties can be achieved through appropriate dynamic homogenization of composites. This homogenization is almost always done for infinite domains and the results are then applied to finite samples. This process ignores the evanescent waves which appear at the boundaries of such finite samples. In this paper we first clarify the emergence and purpose of these evanescent waves in a model problem consisting of an interface between a layered composite and a homogeneous medium. We show that these evanescent waves form boundary layers on either side of the interface beyond which the composite can be represented by appropriate infinite domain homogenized relations. We show that if one ignores the boundary layers then the displacement and stress fields are discontinuous across the interface. Therefore, the scattering coefficients at such an interface cannot be determined through the conventional continuity conditions involving only propagating modes. Here we propose an approximate variational approach for sidestepping these boundary layers. The aim is to determine the scattering coefficients without the knowledge of evanescent modes. Through various numerical examples we show that our technique gives very good estimates of the actual scattering coefficients beyond the long wavelength limit.
Youth Friendly Service Utilization and Associated Factors Among Preparatory School Students in Sodo Town, Southern Nations, Nationalities And Peoples Region, Ethiopia
Creators: name: Atnafu, Natnael
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2017

description: Background: Youth is a period of life in which an individual passes from significant physiological, psychological and social changes that expose them at high risk of reproductive health problems. Even though, there were several strategies approved to solve reproductive health problems of young people including international conference on population development, they still face with unsafe abortion, unintended pregnancy, sexually transmitted infections, acquired human immune deficiency syndrome, lack of provision of condoms and unmet need of family planning. Objective: To assess youth friendly service utilization and factor among preparatory schools students in Sodo Town, Southern Nations, Nationalities, and Peoples Region, Ethiopia 2017. Methods: An institutional based cross-sectional study was conducted among preparatory school students in Sodo Town. Stratified sampling technique was used based on the type of school they had attended. Proportional allocation was done to both government and private schools and to each grade to select 398 respondents. The data was entered with Epi-data version 3.1 and analyzed using SPSS version 22. Descriptive statistics was done and result presented with tables and graphs based on the nature of the variables. Bivariate and multivariate logistic regression was done .The candidate variables with p-value<0.25 in Bivariate analysis were moved to multivariate analysis to identify their significance with dependent variables and those p-Value < 0.05 were taken as independent factors affecting youth friendly service utilization. Result: Out of the total respondents 40.6% reported that they have ever used YFRHS service in the past twelve months. Youth friendly service utilization was significantly associated with sex(AOR:2.106,95%CI:1.115,2.529),pocket money(AOR:0.60,95%CI:0.379,0.949) and using school as a source of information(AOR=0.589,95%CI:0.372,0.933). Conclusion and recommendation: Youth friendly service utilization among preparatory school students in Sodo town was low. Factors like sex, pocket money and school as a source of information were predictors of youth friendly service utilization. Awareness creations on YFRHS and service dimension have to be enhanced. Key Words: Youth friendly Service, Utilization, Sodo Town, Ethiopia.
Kinetics for ozone delignification of oxygen-delignified eucalypt kraft pulp at high consistency
Creators: name: Chapman., Alan Ails
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.
Operationalizing Incomplete Historical Data: Making Reconstruction-Era Tax Records Useful, Accessible, and Comprehensible
Creators: name: Kano, Ami
name: Treene, Rachel Grace
name: Chunru Zheng
Publisher: name: Zenodo
Year: 2023
Subjects: historical data
Mongo
Flask
visualization
sparse data
genealogy
UVA MSDS 2023

description: Incomplete historical data can provide unique challenges to data analysis. However, it is crucial to explore this data for the information it can provide. In this project, personal property tax records from 1867 Virginia are operationalized. The data is cleaned, modeled appropriately, and made publicly accessible with a Flask web application. The project is made scalable by storing the data in a cloud database and writing query and visualization functions that can adapt to new data features. The data is demonstrated to be useful and informative despite its sparse nature. This is partially done with methods that show how incomplete historical data can be leveraged in the broader context of exploratory analysis, and partially done by making the data explorable for the public, showing that the data can also be useful for individuals and historians.
Factors Affecting Supply Chain Performance Of Nongovernmental Organizations: The Case Of FH Ethiopia
Creators: name: Feleke, Alemtena
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2018

description: Supply chain performance had been a significant area of attraction for researchers. However, studies have established the factors affecting supply chain performance in manufacturing and commercial organizations whose focus is to deliver value to customers in order to make a profit. These seem to be there is a gap and known little on factors that affect NGOs' supply chain performance which need to be assessed and due to varying contexts the findings of such studies may not necessarily apply in humanitarian SC. This study therefore undertook the goal to establish factors affecting the performance of supply chain performance of non-governmental organization in the case of FH Ethiopia. The specific objectives of the study included, the analysis of how procurement activities influence the performance of the organizations supply chain, examine how supplier selection practice in the organization affect SC performance, examine how internal policy and procedure of the organization affects supply chain performance and illustrate how listed external environment affects the performance of supply chain in FH Ethiopia. The study adopted descriptive survey research design and qualitative data targeting seventy one employees from FH Ethiopia. From seventy one issued questionnaires, 59 questionnaires representing 83.1% of the total questionnaires distributed were returned fully completed, while 12 questionnaires were not returned representing 16.9% of the total questions distributed to the respondents. According to Mugenda and Mugenda (2003) a response rate of 70% and over is excellent for analysis and reporting on the opinion of the entire population. Primary data was collected using a questionnaire. Ones the data was collected, the researcher checked for its accuracy, consistency and completeness. The data was presented in frequency tables and percentages and discussed. Data was analyzed using descriptive statistics i.e. Frequencies, percentages, means and standard deviations were presented in the form of both tables and figures. The SPSS version 20 computer software was used to aid the analysis. The finding of study shows those inefficient procurement activities, absence of training and development, absence of quality culture and the stated external environment affects and have negative impact on the organizations supply chain performance. The study findings value to the organization to provide information on those factors affecting supply chain performance based on the result of this study, it can also use as reference for future researchers who will be interested to study the topic and it will contribute filling the knowledge gaps in the area
Evaluation Method and Design Guidance for Direction Finding Antenna Systems
Creators: name: Grundmann, Lukas
name: Manteuffel, Dirk
Publisher: name: arXiv
Year: 2023
Subjects: subject: Signal Processing (eess.SP)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: A deterministic evaluation procedure for multi-port direction finding antennas is proposed. It is based on a direction finding uncertainty parameter, which describes how well different directions of arrival and polarizations are distinguishable. By investigating a simple antenna array, it is shown that the proposed parameter provides additional insight into the behavior of an antenna system, when compared to established methods. Moreover, since the uncertainty parameter is calculated from a set of far fields, it is applicable to port far fields as well as Characteristic Modes. This finding is utilized to derive a design guidance: Starting with a set of Characteristic Mode far fields, the angular distribution of the uncertainty is investigated to verify that no ambiguities are present. Different sets of far fields are compared and the differences regarding their direction finding behavior are visualized and explained using the uncertainty in conjunction with an estimate of the incident field. To quantify these differences, a key performance indicator is introduced that summarizes the direction finding capabilities over a selected angular region. To demonstrate the design process, a multi-mode multi-port antenna with three uncorrelated ports is developed, manufactured and measured.
description: This article has been accepted for publication in IEEE Transactions on Antennas and Propagation. This is the author's version which has not been fully edited and content may change prior to final publication
Nursing Performance and Job Satisfaction Among Nurses in a Secondary Hospital in Riyadh, Saudi Arabia
Creators: name: Ramirez, Rovin Basilio
Publisher: name: Zenodo
Year: 2020
Subjects: subject: Nursing
subject: FOS: Health sciences
subject: Job Satisfaction

description: A rapid change brought by technology and the complexity of the diseases
 shaped the healthcare services around the globe. At the frontlines of these changes are nurses and their required expertise and high standard of nursing performance. In the institution where the study was conducted numerous accounts were raised concerning the performances of nurses. An increased rate of safety events concerning medication error, falls rate, several pressure ulcers developed, and needle stick injuries and a significantly high turnover rate among clinical nurses were recorded. This impelled the researcher to explore the relationship between nursing performance and job satisfaction among nurses in a secondary hospital in Riyadh Saudi Arabia. A descriptive correlational design was utilized in this study. The six
 dimensions of the nursing performance (Schwirian, 1978) and nursing workplace satisfaction tool (Fairbrother et al., 2010) was used to gather the information from n=168 respondents who completed the survey. Data analysis were conducted using SPSS, Statistical Package for the Social Sciences, version 22.0. Descriptive statistics such as percentages, frequencies, means, and standard deviations was utilized describing participants’ demographic data. Pearson-moment correlation and
 Chi-square were used to test the relationships between study variables. Generally, nurses in a secondary hospital in Riyadh Saudi Arabia have higher
 nursing performance and job satisfaction. This is evident by the high scores in each of the tested subscales of nursing performance (leadership, critical care,
 teaching/collaboration, interrelation/communications, planning and evaluation, and professional development) and domains of job satisfaction (intrinsic, extrinsic, and relational). The perceived relationship of nursing performance and the sociodemographic and the perceived job satisfaction and sociodemographic showed no relationship. However, sex or gender has a positive relationship with the relational factor of job satisfaction. There is evidence to conclude that there is no statistically significant correlation between overall job satisfaction and leadership (.059) p value=.445, critical care (.059) p value=.447, teaching (.044) p value= .573, planning & evaluation (070) p value= .367 and communications (.106) p value= .173 of
 nurses. However, there is sufficient evidence to conclude that there is a statistically significant correlation between overall job satisfaction and professional development (.208) p=.007.
description: Masters Thesis
Non-chiral 2d CFT with integer energy levels
Creators: name: Ashrafi, M.
name: Loran, F.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The partition function of 2d conformal field theory is a modular invariant function. It is known that the partition function of a holomorphic CFT whose central charge is a multiple of 24 is a polynomial in the Klein function. In this paper, by using the medium temperature expansion we show that every modular invariant partition function can be mapped to a holomorphic partition function whose structure can be determined similarly. We use this map to study partition function of CFTs with half-integer left and right conformal weights. We show that the corresponding left and right central charges are necessarily multiples of 4. Furthermore, the degree of degeneracy of high-energy levels can be uniquely determined in terms of the degeneracy in the low energy states.
description: v2: 19 pages, few footnotes and a reference added, to appear in JHEP
Sawtooth lattice multiferroic BeCr$_2$O$_4$: Non-collinear magnetic structure and multiple magnetic transitions
Creators: name: Mandujano, Hector Cein
name: Metta, Alejandro
name: Barisic, Neven
name: Zhang, Qiang
name: Tabis, Wojciech
name: Muniraju, Naveen Kumar Chogondahalli
name: Nair, Harikrishnan S.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Noncollinear magnetic structures and multiple magnetic phase transitions in a sawtooth lattice antiferromagnet consisting of Cr$^{3+}$ are experimentally identified in this work, thereby proposing the scenario of magnetism-driven ferroelectricity in a sawtooth lattice. The title compound, BeCr$_2$O$_4$, displays three magnetic phase transitions at low temperatures, at $T_{N1}\approx$ 7.5 K, at $T_{N2}\approx$ 25 K and at $T_{N3}\approx$ 26 K, revealed through magnetic susceptibility, specific heat and neutron diffraction in this work. These magnetic phase transitions are found to be influenced by externally applied magnetic fields. Isothermal magnetization curves at low temperatures below the magnetic transitions indicate the antiferromagnetic nature of \bco\ with two spin-flop-like transitions occurring at $H_{c1}\approx$ 29 kOe and $H_{c2} \approx$ 47 kOe. Our high-resolution X-ray and neutron diffraction studies, performed on single crystal and powder samples unambiguously determined the crystal structure as orthorhombic $Pbnm$. By performing the magnetic superspace group analysis of the neutron diffraction data at low temperatures, the magnetic structure in the temperature range $T_{N3,N2} < T < T_{N1}$ is determined to be the polar magnetic space group, $P21nm.1^{\prime}(00g)0s0s$ with a cycloidal magnetic propagation vector $\textbf{k}_1$ = (0, 0, 0.090(1)). The magnetic structure in the newly identified phase below $T_{N1}$, is determined as $P21/b.1^{\prime}[b](00g)00s$ with the magnetic propagation vector $\textbf{k}_2$ = (0, 0, 0.908(1)). The cycloidal spin structure determined in our work is usually associated with electric polarization, thereby making \bco\ a promising multiferroic belonging to the sparsely populated family of sawtooth lattice antiferromagnets.
description: 24 pages, 5 figures, accepted
Organizational Communication and Employee Work Engagement: The Case of Adama Science and Technology University, Ethiopia
Creators: name: Mulleta, Alemu Disassa
Publisher: name: Ethiopian Journal of Science and Sustainable Development
Year: 2023

description: The purpose of this study was to examine the association between organizational communication and employee work engagement. To this end, quantitative data were collected from 302 participants including 47 managers and 255 non-manager staff of Adama Science and Technology University using standardized Likert scales. Results of the study show that superior-subordinate communication and the opportunity to communicate to the upper manager have a statistically significant moderate positive association with employee work engagement. Nevertheless, results of standard regression analysis revealed that only positive superior communication has significantly contributed to the variation in the level of employee work engagement. Implications of the study include the need to strengthen and maintain positive superior communication while addressing other variables which could affect employee work engagement.
description: Ethiopian Journal of Science and Sustainable Development, Vol 10 No 2 (2023): EJSSD
Electron-spin double resonance of nitrogen-vacancy centers in diamond under strong driving field
Creators: name: Mikawa, Takumi
name: Okaniwa, Ryusei
name: Matsuzaki, Yuichiro
name: Tokuda, Norio
name: Ishi-Hayase, Junko
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The nitrogen-vacancy (NV) center in diamond has been the focus of research efforts because of its suitability for use in applications such as quantum sensing and quantum simulations. Recently, the electron-spin double resonance (ESDR) of NV centers has been exploited for detecting radio-frequency (RF) fields with continuous-wave optically detected magnetic resonance. However, the characteristic phenomenon of ESDR under a strong RF field remains to be fully elucidated. In this study, we theoretically and experimentally analyzed the ESDR spectra under strong RF fields by adopting the Floquet theory. Our analytical and numerical calculations could reproduce the ESDR spectra obtained by measuring the spin-dependent photoluminescence under the continuous application of microwaves and an RF field for a DC bias magnetic field perpendicular to the NV axis. We found that anticrossing structures that appear under a strong RF field are induced by the generation of RF-dressed states owing to the two-RF-photon resonances. Moreover, we found that $2n$-RF-photon resonances were allowed by an unintentional DC bias magnetic field parallel to the NV axis. These results should help in the realization of precise MHz-range AC magnetometry with a wide dynamic range beyond the rotating wave approximation regime as well as Floquet engineering in open quantum systems.
description: 11 pages, 4 figures
"Was verursacht Reichtum?" und weitere Fragen zu Spr 15,16 - mit Hilfe der BHt-Software zu beantworten versucht
Creators: name: Vanoni, Gottfried
Publisher: name: Biblische Notizen
Year: 1970

description: Biblische Notizen, Bd. 85 (1996): Biblische Notizen, Band 85
Two-loop QCD Correction to Massive Spin-2 Resonance $ \to q ~ \bar{q} ~ g $
Creators: name: Ahmed, Taushif
name: Das, Goutam
name: Mathews, Prakash
name: Rana, Narayan
name: Ravindran, V.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Two-loop QCD correction to massive spin-2 Graviton decaying to $q ~ + ~ \bar{q}~ + ~g$ is presented considering a generic universal spin-2 coupling to the SM through the conserved energy-momentum tensor. Such a massive spin-2 particle can arise in extra-dimensional models. The ultraviolet and infrared structure of the QCD amplitudes are studied. In dimensional regularisation, the infrared pole structure is in agreement with Catani's proposal, confirming the universal factorization property of QCD amplitudes, even with the spin-2 tensorial coupling. This computation now completes the full two-loop QCD corrections for the production of a spin-2 in association with a jet.
description: 37 pages, references updated
On Poisson equations with a potential in the whole space for "ergodic" generators
Creators: name: Veretennikov, Alexander
Publisher: name: arXiv
Year: 2016
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60H10, 60J60

description: In earlier papers Poisson equation in the whole space was studied for so called ergodic generators $L$ corresponding to homogeneous Markov diffusions ($X_t, \, t\ge 0$) in $\mathbb R^d$. Solving this equation is one of the main tools for diffusion approximation in the theory of stochastic averaging and homogenisation. Here a similar equation with a potential is considered, firstly because it is natural for PDEs, and secondly with a hope that it may be also useful for some extensions related to homogenization and averaging.
description: 15 pages, 18 references
ELECTRICITY GENERATION PERFORMANCE TEST OF BARE AND COOLED PHOTOVOLTAIC PANELS
Creators: name: Tafesse, Dr. Gezahegn Habtamu
name: Megersa, Chaltu Nagesh
Publisher: name: Ethiopian Journal of Science and Sustainable Development
Year: 2023

description: The solar electricity generation ability of a solar panel drops significantly below the nominal efficiency values as a result of higher operating temperature particular in hot location. The drop in efficiency of solar panels can be enhanced by convectively cooling the solar panel surface temperature using water or air. This paper reports the comparative electric generation performances of two identical photovoltaic panels of nominal electric power rating of 60 W with efficiency of 12% and photon absorption area of 0.945 m × 0.55 m. The tests were conducted by exposing both panels to the sun in parallel, one panel bare (non-cooled) and the other being cooled for three cases of cooling arrangements: continuous water cooling, intermittent water cooling or continuous air cooling. The electric generation performance was determined in terms of electric power output and efficiency after measuring surface temperatures, voltages, and currents of both solar panels from 9 am up to 3 pm. The electric power output and electrical efficiency of the bare and the cooled solar panels were compared with each other. The electric generation ability of the continuously water cooled solar panel was better than the other two cooling mechanism. The day average electric power generated and efficiency increment of 17.02 and 13.33 %, respectively were achieved by the continuously water-cooled solar panel compared to the bare.
description: Ethiopian Journal of Science and Sustainable Development, Vol 10 No 2 (2023): EJSSD
Strain-induced pseudomagnetic field in Dirac semimetal borophene
Creators: name: Zabolotskiy, A. D.
name: Lozovik, Yu. E.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: A tight-binding model of 8-Pmmn borophene, a two-dimensional boron crystal, is developed. We confirm that the crystal hosts massless Dirac fermions and the Dirac points are protected by symmetry. Strain is introduced into the model, and it is shown to induce a pseudomagnetic field vector potential and a scalar potential. The dependence of the potentials on the strain tensor is calculated. The physical effects controlled by pseudomagnetic field are discussed.
description: 7 pages, 4 figures. v2: added references and extended the discussion
Shape optimisation of two-dimensional damage tolerant structures using the finite element alternating method
Creators: name: Chaperon., Paul R.
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.
Problems of Micro and Small Enterprises in Addis Ababa: The Case of Kirkos, Kolfe, and Yeka Sub Cities
Creators: name: Mezgebe, Weldegbriel
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2012

description: This study aimed at identifying the major problems that are associated with the performance of MSEs in Addis Ababa. In the study, both qualitative and quantitative research methods were used. Primary data was obtained using questionnaires and unstructured interviews. Secondary data was also collected from books, journals, past research works, official documents and the internet. Stratified sampling was used to select proportional number of samples from the study area. The analytical strategy used was based on the assumptions developed by previous studies. On the basis of the findings, the major problems facing MSEs in Addis Ababa are lack business plan, lack of formal and informal association, lack of favorable business environment, high cost and shortage of raw materials, lack of proper institutional support, lack of proper marketing practice, and stiff competition among MSEs in the same business line and medium and large companies. The study recommended that Enterprises should train by professionals how to develop business plan; the culture of cooperation, and formal and informal association should be improved by taking the work of successful enterprises as examples; enterprises must develop sufficient marketing skills and diversified their product; enterprises should form a supply chain management and support each other to minimize their raw material related problems; the government should adjust the price of output of MSEs parallel with the increase in cost of raw materials purchased by the MSEs; the favorability of the business environment should be enhanced; the quality and accessibility service of supporting institutions should be enhanced; and conducting continuous research to identify the potential problems of the enterprises.
Managing Data Replication and Distribution in the Fog with FReD
Creators: name: Pfandzelter, Tobias
name: Japke, Nils
name: Schirmer, Trever
name: Hasenburg, Jonathan
name: Bermbach, David
Publisher: name: arXiv
Year: 2023
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: The heterogeneous, geographically distributed infrastructure of fog computing poses challenges in data replication, data distribution, and data mobility for fog applications. Fog computing is still missing the necessary abstractions to manage application data, and fog application developers need to re-implement data management for every new piece of software. Proposed solutions are limited to certain application domains, such as the IoT, are not flexible in regard to network topology, or do not provide the means for applications to control the movement of their data. In this paper, we present FReD, a data replication middleware for the fog. FReD serves as a building block for configurable fog data distribution and enables low-latency, high-bandwidth, and privacy-sensitive applications. FReD is a common data access interface across heterogeneous infrastructure and network topologies, provides transparent and controllable data distribution, and can be integrated with applications from different domains. To evaluate our approach, we present a prototype implementation of FReD and show the benefits of developing with FReD using three case studies of fog computing applications.
Assess Land Cover Change Dynamics and Driving Force in the Western Escarpment of the Rift valley in the Gamo Zone, Southern Ethiopia: An Implication to Biodiversity Conservation and Climate Change Mitigation
Creators: name: Dingamo, Temesgen Dirko
Publisher: name: Ethiopian Journal of Science and Sustainable Development
Year: 2023

description: LULC changes are caused by natural and human alterations of the landscape that could largely affect forest biodiversity and the environment. The study aimed to analyze LULC change dynamics and driving forces in the western escarpment of the rift valley of the Gamo Zone, Southern Ethiopia. Digital satellite images, which are downloaded from USGS, were analyzed using ERDAS Imagine (14) and Arc GIS 10.2 software and supervised image classification was used to generate LULC classification, accuracy assessment, and Normalized Difference Vegetation Index (NDVI). Drivers of LULC change were identified and analyzed. Four land classes were identified such as forest, farmland, settlement and water-wetlands. Settlement and farmlands have increased by 8% and 6%, respectively. On the other hand, both forest and water-wetlands decreased by aerial coverage of 9% and 5%, respectively. The overall accuracy of the study area was 92.86%, 94.22% and 94.3% with a kappa value of 0.902, 0.92 and 0.922, respectively. NDVI values ranged from -0.42 to 0.73. Agricultural expansion (31.4%), expansion of settlement (25.7%) and Fuelwood collection and Charcoal production (22.9%) were the main driving forces that affected the biodiversity of the vegetation in the study area. Integrated land use and policy to protect biodiversity loss, forest degradation and climate change are deemed necessary.
description: Ethiopian Journal of Science and Sustainable Development, Vol 10 No 2 (2023): EJSSD
Mass transfer study of gas-liquid and vapour-liquid systems with microporous membrane modules
Creators: name: Chang., I-Kwang
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.
Testing multilayer-coated polarizing mirrors for the LAMP soft X-ray telescope
Creators: name: Spiga, D.
name: Salmaso, B.
name: She, R.
name: Tayabaly, K.
name: Wen, M.
name: Banham, R.
name: Costa, E.
name: Feng, H.
name: Giglia, A.
name: Huang, Q.
name: Muleri, F.
name: Pareschi, G.
name: Soffitta, P.
name: Tagliaferri, G.
name: Valsecchi, G.
name: Wang, Z.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The LAMP (Lightweight Asymmetry and Magnetism Probe) X-ray telescope is a mission concept to measure the polarization of X-ray astronomical sources at 250 eV via imaging mirrors that reflect at incidence angles near the polarization angle, i.e., 45 deg. Hence, it will require the adoption of multilayer coatings with a few nanometers d-spacing in order to enhance the reflectivity. The nickel electroforming technology has already been successfully used to fabricate the high angular resolution imaging mirrors of the X-ray telescopes SAX, XMM-Newton, and Swift/XRT. We are investigating this consolidated technology as a possible technique to manufacture focusing mirrors for LAMP. Although the very good reflectivity performances of this kind of mirrors were already demonstrated in grazing incidence, the reflectivity and the scattering properties have not been tested directly at the unusually large angle of 45 deg. Other possible substrates are represented by thin glass foils or silicon wafers. In this paper we present the results of the X-ray reflectivity campaign performed at the BEAR beamline of Elettra - Sincrotrone Trieste on multilayer coatings of various composition (Cr/C, Co/C), deposited with different sputtering parameters on nickel, silicon, and glass substrates, using polarized X-rays in the spectral range 240 - 290 eV.
description: Preprint version: the fully published paper can be downloaded at http://dx.doi.org/10.1117/12.2185432
Uma nova abordagem de cifragem com pré-imagens autômatos celulares unidimensionais que utiliza borda pseudoaleatória
Creators: name: Menezes, Felipe Augusto
name: Silva, Eduardo Cassiano da
name: Araújo Lima, Danielli
Publisher: name: figshare
Year: 2022
Subjects: subject: 80402 Data Encryption
subject: FOS: Computer and information sciences

description: Tendo em vista o crescimento tecnológico a partir do século XX, diversas tecnologias e meios de comunicação foram criados, o acesso a informação nunca foi tão simples. Devido a isso, podemos nos comunicar através de textos, imagens, áudios com pessoas que estejam do outro lado do mundo instantaneamente. Com isso é necessário obter uma forte segurança dessa comunicação, a partir de criptografia, uma vez que dependendo do conteúdo da informação, poderá trazer prejuízos a um indivíduo ou a um grupo. Os autômatos celulares têm grande aplicabilidade em criptografia, uma vez que são sistemas dinâmicos emergentes e são associados à teoria do caos, propriedades adequadas a bons sistemas criptográficos. Este trabalho tem como objetivo otimizar o algoritmo de criptografia BCCA a fim de obter resultados mais satisfatórios através da aplicação de uma borda pseudoaleatória gerada por uma regra caótica de autômatos celulares.
title: Headache and Sickle Cell Disease: A Scoping Review Protocol
title: Headache SCD Protocol
titleType: AlternativeTitle
Creators: name: Joshi, Aditi
name: Gorelick, Philip
name: Wescott, Annie
name: Curran, Yvonne
name: Jia, Dan Tong
name: Grewal, Prabhjot Kaur
name: Barnett, Thomas
Publisher: name: Prism. Galter Health Sciences Library. Northwestern University
Year: 2023
Subjects: subject: Headache
subject: Sickle cell anemia
subject: Anemia, Sickle Cell

description: Protocol for a scoping review that aims to explore characteristics and prevalence of headache occurring in patients with sickle cell disease.
Local fractality: the case of forest fires in Portugal
Creators: name: Kanevski, Mikhail
name: Pereira, Mário G.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: The research deals with a study of local fractality in spatial distribution of forest fires in Portugal using the sandbox method. The general procedure is the following: (a) define a circle centred in each and all events with increasing radius R; (b) count the number of other events located within the circle of radius R, N(R); (c) plot the growth curve which is the functional dependence of N(R) versus R; and (d) estimate the local fractal dimension as the slope on log[N(R)] versus log[R]. The computation is carried out by using the location of every fire event as a centre but without the final averaging over all the fires for a given R, which is usually performed to get a global fractal dimension and to estimate global clustering. Sandbox method is widely used in many applications in physics and other subjects. The local procedure has the ability to provide the most complete information regarding the spatial distribution of clustering and avoiding non-homogeneity and non-stationarity problems. Most of the analysis was performed using the National Mapping Burnt Area (NMBA) database which accounts for 32,156 fires during the 1975 - 2013 period. The results of local analysis are compared with a randomly generated pattern in forest zones (validity domain). The results demonstrate interesting local spatial patterns of clustering. Some results on global measures are reported as well.
description: 22 pages, 9 figures
Determinants of Rural-Urban Migrants’ Employment Choice in Urban Labor Market: Study from Cities in Central Oromia, Ethiopia
Creators: name: Beriso, Oumer
Publisher: name: Ethiopian Journal of Science and Sustainable Development
Year: 2023

description: Abstract This study investigates the determinants of rural-urban migrants’ employment choices in the urban labor market in central Oromia cities, Ethiopia. The study used a cross-sectional data obtained from rural-to-urban youth migrants, and it estimated multinomial logistic regression to analyze the data. For this purpose, after the urban labor market had been categorized into five urban employment segments, a multinomial logit model was employed to identify factors determining migrants’ job choices from these employment segments. The finding reveals that a migrant’s sex and his/her parent’s annual income have positive significant effects on all employment segments. Migrant’s marriage, information deficiency on job availability, being from small urban area, and father’s occupation have significant positive effects on self-employment, while lack of a city’s identification card for the immigrant and dispute in the city have significant negative effects on the segment. Migrant’s duration of living in cities, information deficiency on job availability, and father’s education and occupation have significant positive effects on informal private-employment. On the contrary, marriage, household size, and lack of identification card have negative impacts on the segment. A migrant’s age, preparatory schooling level, university education, access to registration, and advisory services in the city have significant positive effects on both (private and public) formal employments. The paper has made conclusions and drawn policy implications for possible interventions to urban labor market constraints.
description: Ethiopian Journal of Science and Sustainable Development, Vol 10 No 1 (2023): EJSSD
Market Structure, Conduct and Performance Paradigm Re-applied to the Ethiopian Cement Industry
Creators: name: Thomas, Sisay
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2012

description: This paper presents a market structure, conduct, performance (SCP) analysis of industrial economics to study the relationships that existed between market structure, conduct and performance within the Ethiopian cement industry by employing a simultaneous equations framework. Based on data gathered from twelve cement manufacturing industries for five years, the paper has developed market share, advertising and profitability equations as its three simultaneous equations and estimates the coefficients using Three Stage Least Squares (3SLS) estimation method. Though estimation of the system uses a small number of observations and lacks data on additional instrumental variables the main 3SLS results from the analysis of the system of equations are found out to be : (1) there is a positive, significant and two way causes and effects relationship between market structure (market shares) and firms' strategic behavior (advertising intensity); (2) a similar positive and two way causes and effects relationship is found between profitability and advertising intensity; and (3) there is no any significant effect of market structure on firms profitability though the latter affects the former negatively and significantly. Key words: Cement Industry, market structure, conduct, performance.
Kinetic analysis of spin current contribution to spectrum of electromagnetic waves in spin-1/2 plasma, Part I: Dielectric permeability tensor for magnetized plasmas
Creators: name: Andreev, Pavel A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: The dielectric permeability tensor for spin polarized plasmas is derived in terms of the spin-1/2 quantum kinetic model in six-dimensional phase space. Expressions for the distribution function and spin distribution function are derived in linear approximations on the path of dielectric permeability tensor derivation. The dielectric permeability tensor is derived the spin-polarized degenerate electron gas. It is also discussed at the finite temperature regime, where the equilibrium distribution function is presented by the spin-polarized Fermi-Dirac distribution. Consideration of the spin-polarized equilibrium states opens possibilities for the kinetic modeling of the thermal spin current contribution in the plasma dynamics.
description: 10 pages