1,332 research outputs found
Competing Interactions among Supramolecular Structures on Surfaces
A simple model was constructed to describe the polar ordering of
non-centrosymmetric supramolecular aggregates formed by self assembling
triblock rodcoil polymers. The aggregates are modeled as dipoles in a lattice
with an Ising-like penalty associated with reversing the orientation of nearest
neighbor dipoles. The choice of the potentials is based on experimental results
and structural features of the supramolecular objects. For films of finite
thickness, we find a periodic structure along an arbitrary direction
perpendicular to the substrate normal, where the repeat unit is composed of two
equal width domains with dipole up and dipole down configuration. When a short
range interaction between the surface and the dipoles is included the balance
between the up and down dipole domains is broken. Our results suggest that due
to surface effects, films of finite thickness have a none zero macroscopic
polarization, and that the polarization per unit volume appears to be a
function of film thickness.Comment: 3 pages, 3 eps figure
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Client-server-based LBS architecture: A novel positioning module for improved positioning performance
Permission to distribute obtained from publisher.This work presents a new efficient positioning module that operates over client-server LBS architectures. The
aim of the proposed module is to fulfil the position information requirements for LBS pedestrian applications
by ensuring the availability of reliable, highly accurate and precise position solutions based on GPS single
frequency (L1) positioning service. The positioning module operates at both LBS architecture sides; the client
(mobile device), and the server (positioning server). At the server side, the positioning module is responsible
for correcting user’s location information based on WADGPS corrections. In addition, at the mobile side,
the positioning module is continually in charge for monitoring the integrity and available of the position
solutions as well as managing the communication with the server. The integrity monitoring was based on
EGNOS integrity methods. A prototype of the proposed module was developed and used in experimental trials
to evaluate the efficiency of the module in terms of the achieved positioning performance. The positioning
module was capable of achieving a horizontal accuracy of less than 2 meters with a 95% confidence level
with integrity improvement of more than 30% from existing GPS/EGNOS services
First record of Aequorea globosa Eschscholtz, 1829 (Cnidaria: Hydrozoa) in the coast of Syria
The Indo-Pacific jellyfish Aequorea globosa Eschscholtz, 1829 was reported last year for the first time in the Mediterranean Sea from Iskenderun Bay (S. Turkey). This jellyfish was observed in the coast of Syria, on 8 January 2012, during a regular monthly sampling program
The Effect of Time-Delay Feedback Controller on an Electrically Actuated Resonator
This paper presents a study of the effect of a time-delay feedback controller on the dynamics of a Microelectromechanical systems (MEMS) capacitor actuated by DC and AC voltages. It is shown that negative time-delay feedback control gain can lead to an unstable system, even if AC voltage is relatively small compared to DC voltage. Perturbation method is utilized to present analytically the nonlinear dynamic characteristics of the MEMS capacitor. Agreements among the results of a shooting technique, long-time integration, basin of attraction analysis with the perturbation method are achieved
System Identification and Seismic Performance Evaluation of Earth Dams
A system identification technique is developed to provide dynamic properties of earth dams from their seismic records. The technique is utilized to assess the capabilities and limitation of analytical models in terms of dynamic nonlinear constitutive relationships as well as damping. The technique is based on the least square method using Gaussian hypothesis. Earth dams are modeled as a three-dimensional nonhomogeneous visco-elasto-plastic soil structure. The forward problem is solved using a Galerkin-Ritz formulation in which the solution is expanded using basis function, which is selected to be the eigenmodes. The spatial variation of the excitation is considered by using global shape functions defined on the boundary domain to interpolate the input motion on the dam boundaries using recorded motion at discrete locations. The constitutive model is used to accommodate the nonlinear path dependent behavior of the dam material as well as coupling between different constituent of the soil mixture. The model is implemented using Druker-Prager multi-yield surface model and linear Kelvin-Voigt model. Application to instrumented dams, in recent earthquake, showed significant match between the recorded response and the optimal estimated response
Tingkat Adopsi Inovasi Biosecurity Ayam Ras Petelur di Kabupaten Sidrap dan Faktor- Faktor yang Mempengaruhi
Dalam rangka mendorong adopsi inovasi biosekuriti oleh peternak ayam ras petelur, maka diperlukan pemahaman tentang adopsi inovasi biosecurity ayam ras petelur dan faktor-faktor yang mempengaruhinya. Penelitian ini bertujuan untuk mengetahui tingkat adopsi inovasi biosecurity ayam ras petelur serta faktor-faktor yang mempengaruhinya. Metode penelitian ini adalah pembobotan biosecurity yang terdiri dari biosecurity sumber ayam, biosecurity hewan pengganggu, biosecurity tamu dan pekerja, biosecurity hewan sakit, biosecurity pakan, biosecurity limbah dan biosecurity rak telur, sedangkan untuk faktor-faktor yang mempengaruhi adopsi inovasi biosecurity menggunakan statistika infrensial dengan uji F dan uji t. Hasil penelitian diketahui tingkat adopsi inovasi biosecurity ayam ras petelur di kabupaten Sidrap rendah pada biosecurity terhadap ternak pengganggu sebanyak 59 orang atau 67,82% dan biosecurity tamu dan pekerja sebanyak 59 orang atau 67,82% sedangkan untuk faktor yang mempengaruhi tingkat adopsi inovasi adalah skala USAha dan kontrol perilaku. Kesimpulan dari hasil penelitian adalah ada dua faktor yang mempengaruhi tingkat adopsi inovasi ayam ras petelur di kabupaten Sidrap adalah untuk meningkatkan adopsi inovasi biosecurity dapat dimulai pada skala USAha yang lebih besar dan kemampuan peternak untuk mengkontrol perilakunya
Infeksi Japanese Encephalitis pada Babi di Beberapa Provinsi Indonesia Tahun 2012
Kasus Japanese Encephalitis pada manusia di Indonesia telah ditemukan di beberapa provinsi.Penelitian ini bertujuan untuk mengetahui besarnya angka infeksi JE pada babi sebagai reservoirutama. Penelitian dilakukan di 12 provinsi yang meliputi 15 kabupaten/kota pada tahun 2012. Jumlahseluruh babi yang diperiksa adalah 726 ekor yang terdiri dari 59-62 ekor di tiap provinsi. Darah venadiambil dari tiap ekor babi dan diperiksa dengan Enzyme Link Immuno-Sorbent Assay (ELISA). Jeniskelamin, umur dan lingkungan peternakan babi juga dicatat. Hasil menunjukkan bahwa prevalensi JEpada seluruh babi adalah 14,2 % (103 ekor) yang berkisar antara 1,7 % (1/60) di Provinsi KalimantanTengah dan 32,3 % (20/62) di Provinsi Sulawesi Tengah. Kisaran angka infeksi menurut kabupaten/kota adalah antara 0 % (0/19) di Palangkaraya (Kalimantan Tengah) dan 33,3 % (2/6) di Batanghari(Lampung). Jenis kelamin dan umur babi tidak berhubungan secara signifian dengan besarnya angkainfeksi JE pada babi. Angka infeksi pada babi berbeda bermakna menurut lingkungan, dimana angkainfeksi tertinggi adalah di sekitar danau/setu dan terendah di sekitar pantai. Disimpulkan bahwa babidi 12 provinsi tersebut potensial sebagai sumber infeksi JE ke manusia. Sebab itu perlu dilakukanadvokasi tentang ancaman penularan JE tersebut ke pemerintah daerah dan masyarakat di sekitarpeternakan babi di daerah penelitian, kecuali di Palangkaraya
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