3,618 research outputs found

    Developing Sustainable Life Support System Concepts

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    Sustainable spacecraft life support concepts may allow the development of more reliable technologies for long duration space missions. Currently, life support technologies at different levels of development are not well evaluated against each other, and evaluation methods do not account for long term reliability and sustainability of the hardware. This paper presents point-of-departure sustainability evaluation criteria for life support systems, that may allow more robust technology development, testing and comparison. An example sustainable water recovery system concept is presented

    Kajian Yuridis Terhadap Pekerja Anak Dibawah Umur Menurut Undang-undang Nomor 35 Tahun 2014 Tentang Perubahan Undang-undang Nomor 23 Tahun 2002

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    Tujuan dilakukannya penelitian ini adalah untuk mengetahuibagaimana perlindungan hukum atas keterlibatan anak dibawah umur sebagai pekerja dalam dunia pekerjaan dan bagaimana pemerintah melaksanakan perlindungan bagi pekerja anak melalui sarana dan prasarana. Dengan menggunakan metode penelitian yuridis normative disimpulkan: 1. Secara yuridis peraturan Perundang-undangan Indonesia sudah memberikan kesempatan untuk anak bekerja, setiap anak yang berlatar belakang ekonomi lemah ataupun berdasarkan faktor-faktor lain yang mendukung, anak di izinkan untuk bekerja dengan batasan-batasan tertentu untuk mendukung pertumbuhan dan perkembangannya dan anak harus tetap melanjutkan pendidikan sekolah dasar untuk masa depan anak nanti, serta dalam pelaksanaan kerja anak juga mendapatkan perlindungan kerja dari Perusahan, berupa: tuntunan; santunan; mendapatkan pengakuan hak-hak asasi manusia; mendapat perlindungan fisik; dan sosial ekonomi.2. Secara yuridis anak diizinkan untuk bekerja, tetapi pengawasan terhadap keterlibatan anak dalam suatu proses pelaksanaan kegiatan kerja masih sangat kurang dilakukan oleh pemerintah yang menyebabkan banyak pengusaha atau pemberi kerja melanggar hak-hak anak yang diberikan undang-undang, maka perlu adanya sebuah sarana dan prasarana khusus untuk pekerja anak, seperti: tempat pembuatan karya seni; tempat pengadaan buku-buku pelajaran; tempat pengelolaan budidaya tanaman; dan tempat pekerjaan lain yang tidak membutuhkan banyak waktu ketika melakukan pekerjaan, sehingga tidak mengganggu persekolahan dan tumbuh kembang anak. Kata kunci: Pekerja, anak, dibawah umur

    Extracting the Single-Particle Gap in Carbon Nanotubes with Lattice Quantum Monte Carlo

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    We show how lattice Quantum Monte Carlo simulations can be used to calculate electronic properties of carbon nanotubes in the presence of strong electron-electron correlations. We employ the path integral formalism and use methods developed within the lattice QCD community for our numerical work and compare our results to empirical data of the Anti-Ferromagnetic Mott Insulating gap in large diameter tubes.Comment: 8 pages, 5 figures, Lat2017 proceedin

    Developing Sustainable Spacecraft Water Management Systems

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    It is well recognized that water handling systems used in a spacecraft are prone to failure caused by biofouling and mineral scaling, which can clog mechanical systems and degrade the performance of capillary-based technologies. Long duration spaceflight applications, such as extended stays at a Lunar Outpost or during a Mars transit mission, will increasingly benefit from hardware that is generally more robust and operationally sustainable overtime. This paper presents potential design and testing considerations for improving the reliability of water handling technologies for exploration spacecraft. Our application of interest is to devise a spacecraft wastewater management system wherein fouling can be accommodated by design attributes of the management hardware, rather than implementing some means of preventing its occurrence

    Chemical mechanical polishing of thin film diamond

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    The demonstration that Nanocrystalline Diamond (NCD) can retain the superior Young's modulus (1,100 GPa) of single crystal diamond twinned with its ability to be grown at low temperatures (<450 {\deg}C) has driven a revival into the growth and applications of NCD thin films. However, owing to the competitive growth of crystals the resulting film has a roughness that evolves with film thickness, preventing NCD films from reaching their full potential in devices where a smooth film is required. To reduce this roughness, films have been polished using Chemical Mechanical Polishing (CMP). A Logitech Tribo CMP tool equipped with a polyurethane/polyester polishing cloth and an alkaline colloidal silica polishing fluid has been used to polish NCD films. The resulting films have been characterised with Atomic Force Microscopy, Scanning Electron Microscopy and X-ray Photoelectron Spectroscopy. Root mean square roughness values have been reduced from 18.3 nm to 1.7 nm over 25 {\mu}m2^2, with roughness values as low as 0.42 nm over ~ 0.25 {\mu}m2^2. A polishing mechanism of wet oxidation of the surface, attachment of silica particles and subsequent shearing away of carbon has also been proposed.Comment: 6 pages, 6 figure

    Reusing Data and Metadata to Create New Metadata Through Machine-Learning & Other Programmatic Methods

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    Recent improvements in natural language processing (NLP) enable metadata to be created programmatically from reused original metadata or even the dataset itself. Transfer-learning applied to NLP has greatly improved performance and reduced training data requirements. In this talk, well compare machine-generated metadata to human-generated metadata and discuss characteristics of metadata and data archives that affect suitability for machine-learning reuse of metadata. Where as human-generated metadata is often populated once, populated from the perspective of data supplier, populated by many individuals with different words for the same thing, and limited in length, machine-generated metadata can be updated any number of times, generated from the perspective of any user, constrained to a standardized set of terms that can be evolved over time, and be any length required. Machine-learning generated metadata offers benefits but also additional needs in terms of version control, process transparency, human-computer interaction, and IT requirements. As a successful example, well discuss how a dataset of abstracts and associated human-tagged keywords from a standardized list of several thousand keywords were used to create a machine-learning model that predicted keyword metadata for open-source code projects on code.nasa.gov. Well also discuss a less successful example from data.nasa.gov to show how data archive architecture and characteristics of initial metadata can be strong controls on how easy it is to leverage programmatic methods to reuse metadata to create additional metadata

    Frequency of cannabis and illicit opioid use among people who use drugs and report chronic pain: A longitudinal analysis.

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    BACKGROUND:Ecological research suggests that increased access to cannabis may facilitate reductions in opioid use and harms, and medical cannabis patients describe the substitution of opioids with cannabis for pain management. However, there is a lack of research using individual-level data to explore this question. We aimed to investigate the longitudinal association between frequency of cannabis use and illicit opioid use among people who use drugs (PWUD) experiencing chronic pain. METHODS AND FINDINGS:This study included data from people in 2 prospective cohorts of PWUD in Vancouver, Canada, who reported major or persistent pain from June 1, 2014, to December 1, 2017 (n = 1,152). We used descriptive statistics to examine reasons for cannabis use and a multivariable generalized linear mixed-effects model to estimate the relationship between daily (once or more per day) cannabis use and daily illicit opioid use. There were 424 (36.8%) women in the study, and the median age at baseline was 49.3 years (IQR 42.3-54.9). In total, 455 (40%) reported daily illicit opioid use, and 410 (36%) reported daily cannabis use during at least one 6-month follow-up period. The most commonly reported therapeutic reasons for cannabis use were pain (36%), sleep (35%), stress (31%), and nausea (30%). After adjusting for demographic characteristics, substance use, and health-related factors, daily cannabis use was associated with significantly lower odds of daily illicit opioid use (adjusted odds ratio 0.50, 95% CI 0.34-0.74, p &lt; 0.001). Limitations of the study included self-reported measures of substance use and chronic pain, and a lack of data for cannabis preparations, dosages, and modes of administration. CONCLUSIONS:We observed an independent negative association between frequent cannabis use and frequent illicit opioid use among PWUD with chronic pain. These findings provide longitudinal observational evidence that cannabis may serve as an adjunct to or substitute for illicit opioid use among PWUD with chronic pain

    Safety Review Panel (SRP) Special Topic Presentation on the Iodine Compatible Water Container (ICWC)

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    This viewgraph presentation reviews the safety requirements for the Iodine Compatible Water Container (ICWC). The topics include: 1) ICWC Team; 2) Purpose of presentation; 3) Background/Description of ICWC System; 4) Current status of ICWC Project; 5) HTV launch NCR Processing; 6) Tox 1 containment NCR processing; and 7) ISS on-orbit failure propagation and fault tolerance NCR processing

    Systems and methods for separating a multiphase fluid

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    Apparatus and methods for separating a fluid are provided. The apparatus can include a separator and a collector having an internal volume defined at least in part by one or more surfaces narrowing toward a bottom portion of the volume. The separator can include an exit port oriented toward the bottom portion of the volume. The internal volume can receive a fluid expelled from the separator into a flow path in the collector and the flow path can include at least two directional transitions within the collector
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