1,824 research outputs found
Field operations with cesium clocks in HF navigation systems
Networks of HF phase comparison marine navigation stations employing cesium clocks are discussed. The largest permanent network is in the Gulf of Mexico where some fourteen base stations are continuously active and others are activated as needed. These HF phase comparison systems, which operate on a single transmission path, require a clock on the mobile unit as well. Inventory consists of upwards of 70 clocks from two different manufacturers. The maintenance of this network as an operating system requires a coordinated effort involving clock preparation, clock environment control, station performance monitoring and field service
Resolving the Axial Mass Anomaly in neutrino Scattering
We present a parametrization of the observed enhancement in the transverse
electron quasielastic (QE) response function for nucleons bound in carbon as a
function of the square of the four momentum transfer (Q2) in terms of a
correction to the magnetic form factors of bound nucleons. The parametrization
should also be applicable to the transverse cross section in neutrino
scattering. If the transverse enhancement originates from meson exchange
currents (MEC), then it is theoretically expected that any enhancement in the
longitudinal or axial contributions is small. We present the predictions of the
"Transverse Enhancement" model (which is based on electron scattering data
only) for the neutrino and anti-neutrino differential and total QE cross
sections for nucleons bound in carbon. The 2Q2 dependence of the transverse
enhancement is observed to resolve much of the long standing discrepancy
("Axial Mass Anomaly}) in the QE total cross sections and differential
distributions between low energy and high energy neutrino experiments on
nuclear targets.Comment: 3 pages, 3 Figures, Presented by Arie Bodek at the 19th Particles and
Nuclei International Conference, PANIC 2011, MIT, Cambridge, MA July 201
Analisis Pencahayaan terhadap Kenyamanan Visual pada Pengguna Kantor (Studi Kasus: Kantor PT. Sandimas Intimitra Divisi Marketing di Bekasi)
Manusia pada dasarnya memerlukan cahaya untuk melihat objek secara visual. Cahaya yang dipantulkan oleh objek-objek tersebutlah maka kita dapat melihatnya secara jelas dan mata nyaman untuk melihat. Ruang kerja yang baik adalah ruang kerja yang nyaman untuk melakukan suatu pekerjaan agar hasil kerja optimal. Kenyamanan visual dapat tercapai jika poin-poin Kenyamanan visual teraplikasikan secara optimal antara lain dengan kesesuaian rancangan dengan standar terang yang direkomendasikan dan penataan layout ruangan yang sesuai dengan distribusi pencahayaan. Metode pengumpulan datanya menggunakan metode gabungan (kualitatif dan kuantitatif) dan pengolahan data atau analisa data menggunakan metode komparatif, digunakan untuk menganalisa pencahayaan untuk Kenyamanan visual pada pengguna kantor PT. Sandimas Intimitra Bekasi divisi marketing. Metode gabungan terbagi dari metode kualitatif (kuesioner responden diolah metode likert) dan kuantitatif (pengukuran intensitas cahaya). Metode komparatif membandingkan hasil kuesioner, hasil pengukuran intensitas cahaya dan standart SNI. Hasil dari penelitian ini, berdasarkan pengukuran intensitas cahaya ruangan dan respon dari pengguna ruang dari kuesioner. Maka dihasilkan zona A sudah mencapai standart SNI ruang kantor 350lux pada kondisi tirai terbuka. Yaitu dengan nilai zona A1 365 lux, zona A2 365.33 lux dan zona A3 341.33 lux serta responden menyatakan nyaman. Kemudian pada zona B mencapai standar SNI pada kondisi tirai tertutup dengan hasil zona B1 347.67 lux, zona B2 350.67 lux dan zona B3 355 lux serta pada kondisi ini responden merasa nyaman
Q^2 Evolution of Generalized Baldin Sum Rule for the Proton
The generalized Baldin sum rule for virtual photon scattering, the
unpolarized analogy of the generalized Gerasimov-Drell-Hearn integral, provides
an important way to investigate the transition between perturbative QCD and
hadronic descriptions of nucleon structure. This sum rule requires integration
of the nucleon structure function F_1, which until recently had not been
measured at low Q^2 and large x, i.e. in the nucleon resonance region. This
work uses new data from inclusive electron-proton scattering in the resonance
region obtained at Jefferson Lab, in combination with SLAC deep inelastic
scattering data, to present first precision measurements of the generalized
Baldin integral for the proton in the Q^2 range of 0.3 to 4.0 GeV^2.Comment: 4 pages, 3 figures, one table; text added, one figure replace
Word-Problem-Solving Interventions for Elementary Students With Learning Disabilities: A Selective Meta-Analysis of the Literature
This meta-analysis assessed the effect of word-problem-solving interventions on the word-problem-solving accuracy of students identified as having a learning disability (LD) or at risk for an LD in kindergarten to the sixth grade. Eighteen randomized control group designed studies met the inclusion criteria. Overall, word-problem-solving interventions yielded a significant positive effect on the word-problem-solving accuracy of students in elementary grades with LD (effect size [ES] = 1.08). Instructional components that underlie effective studies were also identified. Results suggest that peer interaction and transfer instructions yielded large effects on treatment outcomes. Results also suggested that intensive interventions (50-min sessions, 34 total sessions) in Grade 3 regardless of instructional setting yielded the largest ESs. These findings support the need to develop and implement quality evidence-based instruction in classroom settings (Tier 1 instruction) prior to utilizing additional resources for more intensive and individualized intervention
Unpolarized structure functions at Jefferson Lab
Over the past decade measurements of unpolarized structure functions at
Jefferson Lab with unprecedented precision have significantly advanced our
knowledge of nucleon structure. These have for the first time allowed
quantitative tests of the phenomenon of quark-hadron duality, and provided a
deeper understanding of the transition from hadron to quark degrees of freedom
in inclusive scattering. Dedicated Rosenbluth-separation experiments have
yielded high-precision transverse and longitudinal structure functions in
regions previously unexplored, and new techniques have enabled the first
glimpses of the structure of the free neutron, without contamination from
nuclear effects.Comment: 21 pages, 9 figures; typo in Eq. (3) corrected, references added; to
appear in J. Phys. Conf. Proc. "New Insights into the Structure of Matter:
The First Decade of Science at Jefferson Lab", eds. D. Higinbotham, W.
Melnitchouk, A. Thoma
The Suggestibility of Older Witnesses
The present study compares younger and older adult witnesses’ susceptibility to misinformation. Previous research on the misinformation effect has not measured the relationship between the effect and individuals’ perceptions of their own memory abilities. Such perceptions, and general knowledge of one’s own memory processes, are referred to as “metamemory.” In order to examine the relationship between metamemory and the misinformation effect in the present study, participants also completed a questionnaire that assessed their perception of their memory functioning. Although older persons tend to perceive their memories as being faulty, the correlation between self-assessment of memory abilities and actual memory performance is relatively low (Zelinski, Gilewski, & Thompson, 1980). We therefore predicted that there would be a negligible relationship between participants’ self-assessed memory functioning and whether or not they were susceptible to misinformation, for both younger and older adults
Implementasi One TIME Pad Kriptografi Pada Gambar Grayscale Dan Gambar Berwarna
Penyandian pesan melalui teknik kriptografi terus berkembang, salah satunya yaitu penggunaan algoritma One Time
Pad (OTP) yang semula hanya digunakan untuk menyandikan tulisan kini dapat digunakan untuk menyandikan
gambar. OTP merupakan algoritma kriptografi klasik kunci simetris yang sangat aman untuk menyandikan gambar,
bahkan sampai saat ini beklum terpecahkan. Hal ini dikarenakan panjang kunci yang digunakan sama dengan
panjang plainteks yang dalam pengoperasiannya harus dalam keadaan random dan tidak boleh digenerate. Hasil
eksperimen diuji menggunaan Peak Signal to Noise Ratio (PSNR), Bit Error Ratio (BER), Cross Correlation (CC).
Pada kriptografi, nilai PSNR semakin mendekati 0 artinya gambar tersandikan sempurna yang bertolak belakang
dengan watermarking. Pada watermarking nilai PSNR lebih dari 40 dB membuktikan tingkat keberhasilan yang baik.
Makalah ini menyajikan hasil eksperimen pada 24 gambar keabuan dan gambar berwarna untuk proses enkripsi dan
dekripsi. Hasil PSNR proses enkripsi terbaik yaitu 7,4134 dB, BER 26230 sedangkan proses dekripsi berhasil dengan
bukti nilai PSNR infinitive, BER dan MSE dari seluruh gambar bernilai 0. Untuk mengetahui perbedaan gambar asli
dengan gambar hasil kriptografi, perbedaan nilai dari hasil percobaan disajikan dalam bentuk histogram.
Kata Kunci: One Time Pad, Kriptografi, Citra, PSNR, BE
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