104 research outputs found
Neural Attentive Session-based Recommendation
Given e-commerce scenarios that user profiles are invisible, session-based
recommendation is proposed to generate recommendation results from short
sessions. Previous work only considers the user's sequential behavior in the
current session, whereas the user's main purpose in the current session is not
emphasized. In this paper, we propose a novel neural networks framework, i.e.,
Neural Attentive Recommendation Machine (NARM), to tackle this problem.
Specifically, we explore a hybrid encoder with an attention mechanism to model
the user's sequential behavior and capture the user's main purpose in the
current session, which are combined as a unified session representation later.
We then compute the recommendation scores for each candidate item with a
bi-linear matching scheme based on this unified session representation. We
train NARM by jointly learning the item and session representations as well as
their matchings. We carried out extensive experiments on two benchmark
datasets. Our experimental results show that NARM outperforms state-of-the-art
baselines on both datasets. Furthermore, we also find that NARM achieves a
significant improvement on long sessions, which demonstrates its advantages in
modeling the user's sequential behavior and main purpose simultaneously.Comment: Proceedings of the 2017 ACM on Conference on Information and
Knowledge Management. arXiv admin note: text overlap with arXiv:1511.06939,
arXiv:1606.08117 by other author
Terahertz Computed Tomography of NASA Thermal Protection System Materials
A terahertz axial computed tomography system has been developed that uses time domain measurements in order to form cross-sectional image slices and three-dimensional volume renderings of terahertz-transparent materials. The system can inspect samples as large as 0.0283 cubic meters (1 cubic foot) with no safety concerns as for x-ray computed tomography. In this study, the system is evaluated for its ability to detect and characterize flat bottom holes, drilled holes, and embedded voids in foam materials utilized as thermal protection on the external fuel tanks for the Space Shuttle. X-ray micro-computed tomography was also performed on the samples to compare against the terahertz computed tomography results and better define embedded voids. Limits of detectability based on depth and size for the samples used in this study are loosely defined. Image sharpness and morphology characterization ability for terahertz computed tomography are qualitatively described
APLIKASI E-TILANG KENDARAAN BERMOTOR BERBASIS ANDROID DI POLSEK SUKOMORO
Sistem tilang selama ini masih menggunakan media kertas yang berwarna merah dan biru. Sidang yang dilakukan di pengadilan tidak terlepas dari oknum calo dan oknum pengadilan yang meminta pemungutan liar terhadap pelanggaran yang telah dilakukan pelanggar lalu lintas. Pelanggaran dalam berkendara di Nganjuk saat ini masih banyak pengendara yang mengabaikan peraturan lalu lintas, sehingga kasus pelanggaran dan resiko kecelakaan yang tinggi maka harus dilakukan tindakan lebih lanjut. Berbagai jenis teknologi semakin berkembang dan tidak terhitung jumlahkanya akan sangat mudah ditemukan pada era modern saat ini salah satunya Android. Saat ini hampir semua orang memiliki Android yang difungsikan sebagai alat komunikasi. Tilang yang dilakukan kepolisian sangat sering jumpai di jalan raya. Hampir setiap hari di setiap daerah tilang kendaraan selalu dilakukan. Tilang yang yang dilakukan dengan cara manual di masa digital seperti ini kurang efektif dijalankan. Tilang secara manual memerlukan waktu yang banyak untuk mendata ulang serta data tersebut sampai kejaksaan. Oleh karena itu, diperlukan system berbasis Android yang dapat mempermudah apparat kepolisian untuk mendata pelanggaran yang terjadi di jalan raya oleh pengendara kendaraan bermotor khususnya di kota Nganjuk. Pengujian aplikasi e-tilang ini dilakukan dengan menggunakan pengujian black box dan memberikan hasil yang sesuai dengan perancangan system
Nonequilibrium spectral diffusion due to laser heating in stimulated photon echo spectroscopy of low temperature glasses
A quantitative theory is developed, which accounts for heating artifacts in
three-pulse photon echo (3PE) experiments. The heat diffusion equation is
solved and the average value of the temperature in the focal volume of the
laser is determined as a function of the 3PE waiting time. This temperature is
used in the framework of nonequilibrium spectral diffusion theory to calculate
the effective homogeneous linewidth of an ensemble of probe molecules embedded
in an amorphous host. The theory fits recently observed plateaus and bumps
without introducing a gap in the distribution function of flip rates of the
two-level systems or any other major modification of the standard tunneling
model.Comment: 10 pages, Revtex, 6 eps-figures, accepted for publication in Phys.
Rev.
A metamaterial absorber for the terahertz regime: Design, fabrication and characterization
We present a metamaterial that acts as a strongly resonant absorber at
terahertz frequencies. Our design consists of a bilayer unit cell which allows
for maximization of the absorption through independent tuning of the electrical
permittivity and magnetic permeability. An experimental absorptivity of 70% at
1.3 terahertz is demonstrated. We utilize only a single unit cell in the
propagation direction, thus achieving an absorption coefficient = 2000
cm. These metamaterials are promising candidates as absorbing elements
for thermally based THz imaging, due to their relatively low volume, low
density, and narrow band response
Recommended from our members
DOE-NSF-NIH Workshop on Opportunities in THz Science, February 12-14, 2004
This is the report of the Workshop on Opportunities in THz Science, held on February 12-14, 2004 in Arlington, VA. This workshop brought together researchers who use or produce THz radiation for physics, chemistry, biology, medicine, and materials science to discuss new research opportunities and common resource needs. The charge from the sponsors of the workshop was to focus on basic science questions within these disciplines that have and can be answered using THz radiation
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