14,029 research outputs found

    Suspending test masses in terrestrial millihertz gravitational-wave detectors: a case study with a magnetic assisted torsion pendulum

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    Current terrestrial gravitational-wave detectors operate at frequencies above 10 Hz. There is strong astrophysical motivation to construct low-frequency gravitational-wave detectors capable of observing 10 mHz - 10Hz signals. While space-based detectors provide one means of achieving this end, one may also consider terretrial detectors. However, there are numerous technological challenges. In particular, it is difficult to isolate test masses so that they are both seismically isolated and freely falling under the influence of gravity at millihertz frequencies. We investigate the challenges of low-frequency suspension in a hypothetical terrestrial detector. As a case study, we consider a Magnetically Assisted Gravitational-wave Pendulum Intorsion (MAGPI) suspension design. We construct a noise budget to estimate some of the required specifications. In doing so, we identify what are likely to be a number of generic limiting noise sources for terrestrial millihertz gravitational-wave suspension systems (as well as some peculiar to the MAGPI design). We highlight significant experimental challenges in order to argue that the development of millihertz suspensions will be a daunting task. Any system that relies on magnets faces even greater challenges. Entirely mechanical designs such as Zollner pendulums may provide the best path forward.Comment: 6 pages, 4 figure

    Strapdown inertial measurement unit computer, volume 1 Final report

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    Strapdown inertial measurement unit design, calculations, and operating instruction

    The Relationship Between Internet Marketing, Search Volume, and Product Sales

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    This paper determines whether internet advertisement, and a product’s online popularity, as measured in search queries, can predict sales revenue. To test for correlations, the sales data, ad spending, and Google keyword search volume for Apple’s iPod and iPhone was collected, and developed into a finite distributed lag model. The model for the iPod’s sales revenue shows that there is a strong seasonal effect on sales, and neither the internet popularity, as measured by Google searches, or advertisement spending has a statistically significant effect. The iPhone’s sales revenue is shown to be significantly influenced by the internet popularity, and its lag. The iPhone’s revenue is not significantly affected by advertising or seasonality. The results of this study could be used to determine the effectiveness of advertisement on consumer interest in a product, on the internet. Similar models could be able to determine whether Google search volume can predict the sales revenues of other products.No embarg

    Cloning and Sequencing of a Partial CYPlA Gene in Creek Chub (Semotilus a/romaculatus): The first step in the development of a biomarker of exposure to AhR Ligand

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    Biomarkers are powerful tools that allow scientists to assess exposure of biota to environmental chemicals. In studying the hazardous waste site surrounding the former 3M/Dynacolor plant in Brockport, NY, a biomarker capable of assessing combined exposure to polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) was needed. These compounds, along with polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), mediate toxicity through the arylhydrocarbon receptor, resulting in carcinogenicity and endocrine disruption with obvious human health and environmental risks. The goal of my study was to develop a biomarker of exposure that would allow for the evaluation of the combined exposure to PCBs, PAHs, PCDFs and PCDDs of the creek chub (Semoti!us atromacularus), a common fish in Brockport Creek adjacent to the hazardous waste site. The first step in the preparation of such a biomarker is the sequencing of a portion of the CYP1A gene, a gene induced by the aryl-hydrocarbon receptor. The objectives of my study were to ( l) isolate DNA from creek chub tissue, (2) amplify a segment of the CYP1A gene from genomic DNA using degenerate primers, (3) clone the fragment using the TA cloning technique, and ( 4) sequence the fragment and to compare it phylogenetically with known CYP1A sequences. The sequence of the isolated fragment was homologous with CYP1A genes of teleost fishes, showing high percent identity with portions of the CYP1A gene oft wo members of the same taxonomic family (Cyprinidae), the common carp ( Cyprinus carpio) and the zebrafish (Danio rerio). The isolation of this sequence offers the possibility of developing a biomarker of exposure that measures the amount of CYP1A mRNA induced in various tissues of S. atromaculatus

    Conflict Resolution: U.N. Nonfighting Forces

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    The modern version of peacekeeping really began in 1956 when that UNEF force was first interposed between the two sides after the Suez War, after the shooting stopped, and in a sense it represented a SovietAmerican veto over the use of force by the other powers

    The U.N. and the U.S. National Interest

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    My new assignment is to take a fresh look at the relationship between the U.N. and the U.S. national interest over a time span that sees ahead to the next three to ten years

    Reef-Santa Cruz as Austronesian

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    The Fragile Victory for Unaccompanied Children\u27s Due Process Rights after Flores v. Sessions

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    In 2017, the Ninth Circuit Court of Appeals found that when the federal government detains an unaccompanied child, that child has the right to request legal review of his or her custody before an immigration judge. In Flores v. Sessions, the court reaffirmed the right, which had been present in the text of the laws governing the treatment of immigrant youth, but had been ignored by executive branch bodies. In its analysis, the court considered the relationship between a twenty-year-old settlement and two acts of Congress that govern the treatment of immigrant youth. The Flores decision affects the lives of an incredibly vulnerable population-children who travel to the United States alone, often to flee gang-related and domestic violence-over half of which qualify for protection deriving from international law. This Note analyzes the significance of the Flores v. Sessions decision and the population that it affects. Through the comparison of laws governing children\u27s detention and the due process rights of adults challenging immigration custody decisions, this Note argues that the Flores decision represents a temporary victory for unaccompanied children, albeit one that calls for persistence on the part of advocates as the implementation of bond hearings moves forward

    Political gaming

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    Revision ICaption title"December 21, 1959.""U.S. Army War College, Carlisle Barracks, Pennsylvania, November 20, 1959"--leaf [1]"L2-517"--handwritten on cove
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