77,112 research outputs found
Design Features And Stress Analysis Of A 0.686-Scale Standard Dynamics Model
A 0 .686-Scale Standard Dynamics Model Incorporating Some Tpecial Features Was Designed And Built At NAL .A Brief . Description Of The Various Design And Construction Features, Load Estimations And A Detailed Stress Analysis Of The Model Are Presented In The Report To Provide An Idea Of The Current Practice Adopted At NAL For The Design And Construction Of Wind Tunnel Models For Dynamic Stability Testing . The Model Was Successfully Employed For Check-Out And Validation Of A Forced-Oscillation Rig At Mach Numbers Up to 1.3 And Angles Of Attack Up to 20 Deg In The NAL 1.2m Blowdown Tunne
Recommended from our members
Understanding structure of concurrent actions
Whereas most work in reinforcement learning (RL) ignores the structure or relationships between actions, in this paper we show that exploiting structure in the action space can improve sample efficiency during exploration. To show this we focus on concurrent action spaces where the RL agent selects multiple actions per timestep. Concurrent action spaces are challenging to learn in especially if the number of actions is large as this can lead to a combinatorial explosion of the action space.
This paper proposes two methods: a first approach uses implicit structure to perform high-level action elimination using task-invariant actions; a second approach looks for more explicit structure in the form of action clusters. Both methods are context-free, focusing only on an analysis of the action space and show a significant improvement in policy convergence times
Signal transducer and activator of transcription-1 localizes to the mitochondria and modulates mitophagy
The signal transducer and activator of transcription (STAT) proteins are latent transcription factors that have been shown to be involved in cell proliferation, development, apoptosis, and autophagy. STAT proteins undergo activation by phosphorylation at tyrosine 701 and serine 727 where they translocate to the nucleus to regulate gene expression. STAT1 has been shown to be involved in promoting apoptotic cell death in response to cardiac ischemia/reperfusion and has recently been shown by our laboratory to be involved in negatively regulating autophagy. These processes are thought to promote cell death and restrict cell survival leading to the generation of an infarct. Here we present data that shows STAT1 localizes to the mitochondria and co-immunoprecipitates with LC3. Furthermore, electron microscopy studies also reveal mitochondria from ex vivo I/R treated hearts of STAT1KO mice contained within a double membrane autophagosome indicating that STAT1 may be involved in negatively regulating mitophagy. This is the first description of STAT1 being localized to the mitochondria and also having a role in mitophagy
Improving Search through A3C Reinforcement Learning based Conversational Agent
We develop a reinforcement learning based search assistant which can assist
users through a set of actions and sequence of interactions to enable them
realize their intent. Our approach caters to subjective search where the user
is seeking digital assets such as images which is fundamentally different from
the tasks which have objective and limited search modalities. Labeled
conversational data is generally not available in such search tasks and
training the agent through human interactions can be time consuming. We propose
a stochastic virtual user which impersonates a real user and can be used to
sample user behavior efficiently to train the agent which accelerates the
bootstrapping of the agent. We develop A3C algorithm based context preserving
architecture which enables the agent to provide contextual assistance to the
user. We compare the A3C agent with Q-learning and evaluate its performance on
average rewards and state values it obtains with the virtual user in validation
episodes. Our experiments show that the agent learns to achieve higher rewards
and better states.Comment: 17 pages, 7 figure
Surface immobilization of hexa-histidine-tagged adeno-associated viral vectors for localized gene delivery.
Adeno-associated viral (AAV) vectors, which are undergoing broad exploration in clinical trials, have significant promise for therapeutic gene delivery because of their safety and delivery efficiency. Gene delivery technologies capable of mediating localized gene expression may further enhance the potential of AAV in a variety of therapeutic applications by reducing spread outside a target region, which may thereby reduce off-target side effects. We have genetically engineered an AAV variant capable of binding to surfaces with high affinity through a hexa-histidine metal-binding interaction. This immobilized AAV vector system mediates high-efficiency delivery to cells that contact the surface and thus may have promise for localized gene delivery, which may aid numerous applications of AAV delivery to gene therapy
Analisis Pola dan Struktur Inflasi Kota Medan
Adapun tujuan yang akan dicapai dalam penelitian ini adalah untuk melakukan identifikasi tentang pola inflasi yang terjadi di kota Medan, mengetahui kelompok barang yang berkontribusi besar pada inflasi di kota Medan dan untuk mengetahui faktor-faktor yang mempengaruhi inflasi di kota Medan. jenis data yang digunakan adalah data kuantitatif dengan jenis rasio dan kualitatif. Sedangkan berdasarkan dimensi waktu, maka data yang digunakan adalah data runtun waktu (time serries). Metode analisa data yang digunakan oleh penulis dalam penelitian ini adalah dengan menghitung pertumbuhan ekonomi untuk melihat pola inflasi, dengan menggunakan analisis kuantitatif dengan menggunakan analisa korelasi dan regresi dan dengan menggunakan analisis kualitatif untuk melihat jenis kelompok barang yang mendominasi inflasi di kota Medan.Hasil pembahasan yang diperoleh dari analisa data bahwa laju inflasi di kota Medan dalam kurun waktu tahun 2000-2011 relatif sangat fluktuatif, dengan rata-rata 8,48%. Kemudian dapat kesimpulan bahwa ada hubungan antara konsumsi masyarakat (C), Investasi (I), dan konsumsi pemerintah (G) sebesar 92,4% dengan laju inflasi di kota Medan. Tingkat konsumsi (C) berpengaruh secara positif dan signifikan terhadap laju inflasi, investasi (I) berpengaruh secara positif dan signifikan terhadap laju inflasi dan pengeluaran pemerintah pemerintah kota Medan (G) berpengaruh secara positif dan signifikan terhadap laju inflasi
Radio Spectra and NVSS Maps of Decametric Sources
We constructed radio spectra for ~1400 UTR-2 sources and find that 46% of
them have concave curvature. Inspection of NVSS maps of 700 UTR sources
suggests that half of all UTR sources are either blends of two or more sources
or have an ultra-steep spectrum (USS). The fraction of compact USS sources in
UTR may be near 10%. Using NVSS and the Digitized Sky Survey(s) we expect to
double the UTR optical identification rate from currently ~19%.Comment: 2 pages, no figures; to appear in Proc. "Observational Cosmology with
the New Radio Surveys", eds. M. Bremer, N. Jackson & I. Perez-Fournon, Kluwer
Acad. Pres
High bat (Chiroptera) diversity in the Early Eocene of India
The geographic origin of bats is still unknown, and fossils of earliest bats are rare and poorly diversified, with, maybe, the exception of Europe. The earliest bats are recorded from the Early Eocene of North America, Europe, North Africa and Australia where they seem to appear suddenly and simultaneously. Until now, the oldest record in Asia was from the Middle Eocene. In this paper, we report the discovery of the oldest bat fauna of Asia dating from the Early Eocene of the Cambay Formation at Vastan Lignite Mine in Western India. The fossil taxa are described on the basis of well-preserved fragments of dentaries and lower teeth. The fauna is highly diversified and is represented by seven species belonging to seven genera and at least four families. Two genera and five species are new. Three species exhibit very primitive dental characters, whereas four others indicate more advanced states. Unexpectedly, this fauna presents strong affinities with the European faunas from the French Paris Basin and the German Messel locality. This could result from the limited fossil record of bats in Asia, but could also suggest new palaeobiogeographic scenarios involving the relative position of India during the Early Eocene
Proposal for a Performance Dashboard for the Monitoringof Water and Sewage Service Companies (WaSCs)
The water and sewage industry provides an essential service to the community, but it is characterized by natural monopoly tendencies of service suppliers. In this framework, it is very important to assist regulators with a small set of critical indicators (performance dashboard) for the evaluation and monitoring of the service provided by Water and Sewage Companies (WaSCs). The paper originates from the analysis of situation of Piemonte (Italy), where each regional and local body adopts a proprietary Performance Measurement System (PMS). In order to improve the coordination of information flow and to support the definition of common service standards, a methodology to merge existing PMSs and define a unique shared reference system is proposed. The Kaplan and Norton's Balanced Scorecard (BSC) is adopted as the reference model of this approach. BSC is widely recognized to be an exhaustive and balanced framework in describing the performances of an organization and ensures that all the operational aspects of WaSCs are adequately monitored. The output of the proposed procedure is a general performance dashboard for the monitoring of WaSCs. The dashboard is shown and some remarks about indicators properties are developed. In particular, this analysis highlights some common pitfalls originated by a ârushed' aggregation of several performance indicators. Description is supported by several example
- âŠ