170 research outputs found
Probing dark energy with large galaxy surveys: systematics quantification and mitigation
No full textDark energy is a leading theory to explain cosmic acceleration, and forthcoming astronomical surveys have been specifically designed to probe this mysterious energy component of our universe. This thesis addresses aspects of using large galaxy surveys to study dark energy, which requires an unprecedented understanding and mitigation of systematics -- a challenge that can be addressed on two fronts: quantification of the impacts of systematics, and new tools to mitigate them. Here, we specifically study the impacts of three key systematics: those induced by 1) the telescope observing strategy, 2) the Milky Way dust, and 3) uncertain photometric redshifts. Focusing on the Legacy Survey of Space and Time (LSST) carried out by the Vera C. Rubin Observatory, we quantify the impacts of LSST observing strategy on large-scale structure studies, which is a probe of dark energy. We demonstrate the effectiveness of large translational dithers -- telescope-pointing offsets -- in increasing LSST survey uniformity and reducing systematic uncertainties (Awan et al., 2016; LSST Science Collaboration et al., 2017) -- a result that has now been adopted for the baseline LSST observing strategy. We also study the impacts of Milky Way dust on dark energy science and demonstrate that ~25% of the default LSST survey area would not be useful for extragalactic static science given the Milky Way dust extinction, motivating the reconfiguration of the LSST survey footprint to avoid high-extinction regions of the sky (Lochner et al., 2018; Olsen et al., 2018). And finally, we present a new formalism that provides a novel way to correct for redshift contamination arising from photometric redshift estimation (Awan & Gawiser, 2020). Specifically, we first introduce a general formalism to correct for sample contamination for photometric galaxy samples when measuring two-point angular correlation functions, and then a new weighted estimator that assigns each galaxy a weight in each redshift bin based on its probability of being in that bin, thereby fully utilizing the probabilistic distance information available for photometric galaxies. While these techniques are motivated by preparations for LSST, they are applicable to other large galaxy surveys like Dark Energy Survey (DES), Dark Energy Spectroscopic Instrument (DESI), Hobby-Eberly Telescope Dark Energy Experiment (HETDEX), Euclid, and Wide-Field Infrared Survey Telescope (WFIRST).Ph.D.Includes bibliographical reference
Probing Dark Energy with Large Galaxy Surveys: Systematics Quantification & Mitigation
No full textDark energy is a leading theory to explain cosmic acceleration, and forthcoming astronomical surveys have been specifically designed to probe this mysterious energy component of our universe. This thesis addresses aspects of using large galaxy surveys to study dark energy, which requires an unprecedented understanding and mitigation of systematics -- a challenge that can be addressed on two fronts: quantification of the impacts of systematics, and new tools to mitigate them. Here, we specifically study the impacts of three key systematics: those induced by 1) the telescope observing strategy, 2) the Milky Way dust, and 3) uncertain photometric redshifts. Focusing on the Legacy Survey of Space and Time (LSST) carried out by the Vera C. Rubin Observatory, we quantify the impacts of LSST observing strategy on large-scale structure studies, which is a probe of dark energy. We demonstrate the effectiveness of large translational dithers -- telescope-pointing offsets -- in increasing LSST survey uniformity and reducing systematic uncertainties (Awan et al., 2016; LSST Science Collaboration et al., 2017) -- a result that has now been adopted for the baseline LSST observing strategy. We also study the impacts of Milky Way dust on dark energy science and demonstrate that ~25% of the default LSST survey area would not be useful for extragalactic static science given the Milky Way dust extinction, motivating the reconfiguration of the LSST survey footprint to avoid high-extinction regions of the sky (Lochner et al., 2018; Olsen et al., 2018). And finally, we present a new formalism that provides a novel way to correct for redshift contamination arising from photometric redshift estimation (Awan & Gawiser, 2020). Specifically, we first introduce a general formalism to correct for sample contamination for photometric galaxy samples when measuring two-point angular correlation functions, and then a new weighted estimator that assigns each galaxy a weight in each redshift bin based on its probability of being in that bin, thereby fully utilizing the probabilistic distance information available for photometric galaxies. While these techniques are motivated by preparations for LSST, they are applicable to other large galaxy surveys like Dark Energy Survey (DES), Dark Energy Spectroscopic Instrument (DESI), Hobby-Eberly Telescope Dark Energy Experiment (HETDEX), Euclid, and Wide-Field Infrared Survey Telescope (WFIRST).To be published by ProQuest with a non-exclusive right to distribute
A discrete-time performance model for congestion control mechanism using queue thresholds with QOS constraints
No full textYesThis paper presents a new analytical framework for the congestion control of Internet traffic using a
queue threshold scheme. This framework includes two discrete-time analytical models for the performance
evaluation of a threshold based congestion control mechanism and compares performance measurements through
typical numerical results. To satisfy the low delay along with high throughput, model-I incorporates one
threshold to make the arrival process step reduce from arrival rate ¿1 directly to ¿2 once the number of packets in
the system has reached the threshold value L1. The source operates normally, otherwise. Model-II incorporates
two thresholds to make the arrival rate linearly reduce from ¿1 to ¿2 with system contents when the number of
packets in the system is between two thresholds L1 and L2. The source operates normally with arrival rate ¿1
before threshold L1, and with arrival rate ¿2 after the threshold L2. In both performance models, the mean packet
delay W, probability of packet loss PL and throughput S have been found as functions of the thresholds and
maximum drop probability. The performance comparison results for the two models have also been made
through typical numerical results. The results clearly demonstrate how different load settings can provide
different tradeoffs between throughput, loss probability and delay to suit different service requirements
Performance modelling of a multiple threshold RED mechanism for bursty and correlated Internet traffic with MMPP arrival process
No full textYesAccess to the large web content hosted all over the world by users of the Internet engage
many hosts, routers/switches and faster links. They challenge the internet backbone to operate at
its capacity to assure e±cient content access. This may result in congestion and raises concerns over
various Quality of Service (QoS) issues like high delays, high packet loss and low throughput of the
system for various Internet applications. Thus, there is a need to develop effective congestion control
mechanisms in order to meet various Quality of Service (QoS) related performance parameters. In this
paper, our emphasis is on the Active Queue Management (AQM) mechanisms, particularly Random
Early Detection (RED). We propose a threshold based novel analytical model based on standard RED
mechanism. Various numerical examples are presented for Internet traffic scenarios containing both the
burstiness and correlation properties of the network traffic
ROMANSA CINTA PRAMUGARI, SUATU TINJAUAN PSIKOLOGI KEPRIBADIAN DALAM NOVEL “CINTA DI ATAS AWAN” KARYA GLENN ALEXEI
No full textSidiq Wahyu Nugroho. 2018. "The Romance of Love Stewardess, A Psychological Review of Personality in Glenn Alexei's Love Di Atas Awan Novel". Undergraduate Thesis Indonesian Language and Literature Faculty of Cultural Sciences Diponegoro University Semarang. Advisor: Laura Andri R.M, S.S., M.A. and Fajrul Falah, S.Hum., M.Hum.
This research is a library research, sourced from the novel Cinta di Atas Awan with the problems of the main character who experienced deterioration due to the unrequited love and ended up failing due to the existence of a third party. The deterioration of love makes the main character aware and re-open the heart to others, and ends beautifully with the anchoring of that love to his hardest friend. The author uses a theoretical psychology theory foundation that aims to analyze the personality structure of the main character in the struggle for his true love. The author uses structural theory to obtain data that is intended in the form of intrinsic elements as builders of the story which includes themes, characters and characterizations, plot, background as forming elements of literary works in the novel Cinta di Atas Awan.
The purpose of this study was to reveal the links between structural elements and examine the main character using the psychology theory of personality. The method used is the study of data collection, data analysis studies, and study of the presentation of the results of the analysis. This research produces three elements of psychology, namely id (das es), Karina Id, that is, she cries because the batis is hurt. Karina's ego (das ich) is her desire to remain Jimmy's lover. Super ego (das uber ich) Karina is that she thinks that what she is doing is wrong, that is, expecting something in vain. Karina realized that Alvin had been faithful and loved her. Emotional classification also appears in the study, namely sadness and love and reveals the romance of love.
Keywords: Struggle, Love, Personality, Structure, Psychology
Sistem Informasi Pendaftaran DNA Sexing Report Awan Bird Berbasis Java
No full textInformation technology that is engaged in the DNA Sexing Report test business or registration of the DNA Sexing Report is a system that is still rarely used by businesses engaged in the field of DNA sexing. Awan Bird Business is a business with a registration system and the calculation is still fairly manual where the system has not been computerized. The purpose of this study is to make a design of an application for the DNA Sexing Report Registration Information System that can carry out the registration system activities and DNA test payments and report making more efficiently. The method the author uses to create a DNA Sexing Report registration information system using the programming language Java Netbeans and MySQL. The author uses Java Netbeans IDE 8.0.2 for making programs and MySQL as a database storage facility. The results of the system that was built can facilitate the admin in the process of registering DNA Sexing Report and payment of DNA Sexing Report so that it is easier to find data
Testing LSST dither strategies for Survey Uniformity and Large-Scale Structure Systematics
No full textThe Large Synoptic Survey Telescope (LSST) will survey the southern sky from 2022{2032 with unprecedented detail. Since the observing strategy can lead to artifacts in the data, we investigate the eects of telescope-pointing osets (called dithers) on the r-band coadded 5 depth yielded after the 10-year survey. We analyze this survey depth for several geometric patterns of dithers (e.g.,random, hexagonal lattice, spiral) with amplitude as large as the radius of the LSST eld-of-view, implemented on dierent timescales (per season, per night, per visit). Our results illustrate that per night and per visit dither assignments are more eective than per season. Also, we find that some dither geometries (e.g., hexagonal lattice) are particularly sensitive to the timescale on whichthe dithers are implemented, while others like random dithers perform well on all timescales. We then model the propagation of depth variations to articial uctuations in galaxy counts, which are a systematic for large-scale structure studies. We calculate the bias in galaxy counts caused by the observing strategy, accounting for photometric calibration uncertainties, dust extinction, and magnitude cuts; uncertainties in this bias limit our ability to account for structure induced by the observing strategy. We nd that after 10 years of the LSST survey, the best dither strategies lead to uncertainties in this bias smaller than the minimum statistical floor for a galaxy catalog as deep asr<27.5. A few of these strategies bring the uncertainties close to the statistical floor for r<25.7 after only one year of survey.Fil: Awan, Humna. Rutgers University; Estados UnidosFil: Gawiser, Eric. Rutgers University; Estados UnidosFil: Kurczynski, Peter. Rutgers University; Estados UnidosFil: Lynne Jones, R.. University of Washington; Estados UnidosFil: Zhan, Hu. Chinese Academy of Sciences; República de ChinaFil: Padilla, Nelson David. Pontificia Universidad Católica de Chile; ChileFil: Muñoz Arancibia, Alejandra M.. Pontificia Universidad Católica de Chile; ChileFil: Orsi, Alvaro. Centro de Estudios de Fisica del Cosmos de Aragon; EspañaFil: Cora, Sofia Alejandra. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; ArgentinaFil: Yoachim, Peter. University of Washington; Estados Unido
Horizonless Worlds: Navigating the Persistent Present of the Border Regime
No full textThrough discussing the persistent present of displacement the essay argues that a politics of time is being mobilised as a biopolitical means of control in migrant lives. This can be seen in the circularity of displacement, deportation and return, where waiting and disorientation become forms of control. The discussion emerges from field research and interviews I carried out in the villages of north Punjab, Pakistan, where many people are caught in this chronopolitics of migration. The migrant experience of borders is read alongside a critical interrogation of the computational technologies deployed in border management, including EuroDAC and iMap. They produce a form of imperial temporality for which the horizon acts as a constitutive trope of progress, while simultaneously producing a sense of a horizonless world through the networked logic and ubiquity of datafication. I end with a discussion of how it may be possible to find other orientations within these normative spatiotemporalities of a bordered world.Theory, Territories & Transition
Landscape in Flux: Precision and error of the natural phenomena affecting the coastline
No full textNatural phenomena are continually changing the coastline and sculpting the land in various ways. By surveying these changes a map can be produced of a landscape in flux. But if the landscape is ever changing, what does it tell us about the precision of flux. The essay also tries to give an answer to the question if there can be error in flux or if the essence of flux is made out of error. First it will be introduced by looking at the representability of open source satellite imagery and the intelligence behind the processes they go through. In the process minor errors can appear that can affect our resolution of a place by looking from afar. These errors are tried to make apparent by mapping out three different types of natural phenomena in combination with man made architecture. The topic will be surveyed with the use of a case study surrounding Gwadar, Pakistan.Architecture, Urbanism and Building Sciences | Borders and Territorie
Unbiased Cosmological Parameter Estimation from Emission-Line Surveys with Interlopers
No full textThe galaxy catalogs generated from low-resolution emission-line surveys often contain both foreground and background interlopers due to line misidentification, which can bias the cosmological parameter estimation. In this paper, we present a method for correcting the interloper bias by using the joint analysis of auto- and cross-power spectra of the main and the interloper samples. In particular, we can measure the interloper fractions from the cross-correlation between the interlopers and survey galaxies, because the true cross-correlation must be negligibly small. The estimated interloper fractions, in turn, remove the interloper bias in the cosmological parameter estimation. For example, in the Hobby-Eberly Telescope Dark Energy Experiment low-redshift (z \u3c 0.5) [O ii] λ3727A emitters contaminate high-redshift (1.9 \u3c z \u3c 3.5) Lyα line emitters. We demonstrate that the joint-analysis method yields a high signal-to-noise ratio measurement of the interloper fractions while only marginally increasing the uncertainties in the cosmological parameters relative to the case without interlopers. We also show that the same is true for the high-latitude spectroscopic survey of the Wide-field Infrared Survey Telescope mission where contamination occurs between the Balmer-α line emitters at lower redshifts (1.1 \u3c z \u3c 1.9) and oxygen ([O III] λ5007A) line emitters at higher redshifts (1.7 \u3c z \u3c 2.8)
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