680 research outputs found
EVALUASI KINERJA SISTEM KOMUNIKASI SERAT OPTIK BERDASARKAN TEKNOLOGI DWDM PADA AREA RING-1 JAWA BACKBONE
ABSTRAKSI: Jawa Backbone merupakan jaringan transmisi Sistem Komunikasi Serat Optik (SKSO) yang menghubungkan daerah-daerah yang ada di pulau Jawa dan memiliki peranan yang sangat penting dalam kegiatan komunikasi. Seiring dengan kebutuhan pelanggan akan kegiatan berkomunikasi yang semakin meningkat, terlebih lagi di pulau Jawa yang memiliki kepadatan penduduk yang paling tinggi di Indonesia, maka evaluasi dan peningkatan performansi terhadap SKSO akan selalu dibutuhkan baik dalam segi jaringan transmisi maupun kemampuan perangkat agar kebutuhan pelanggan selalu terpenuhi.Pada tugas akhir ini, dievaluasi kinerja SKSO pada area Jawa Backbone ring-1, di mana teknologi multiplexing yang digunakan adalah Dense Wavelength Division Multiplexing (DWDM). Evaluasi dan analisis dilakukan berdasarkan beberapa parameter yaitu link power budget, rise time budget, maintainability, availability, reliability, dan gangguan yang terjadi.Dari hasil evaluasi selama periode 1 Januari 2009 – 30 April 2010, diketahui nilai MTTR (Repair) rata-rata sebesar 4,87 jam (memenuhi standar), nilai MTTR (Recovery) rata-rata sebesar 9,69 jam (tidak memenuhi standar), dan availability rata-rata sistem sebesar 99,67% (tidak memenuhi standar). Hal ini menandakan bahwa kualitas performansi sistem belum cukup baik. Diketahui juga selama periode tersebut, gangguan dominan yang terjadi adalah kabel putus yang disebabkan oleh pihak ke-3.Kata Kunci : SKSO, Jawa Backbone ring-1, DWDM, performansi.ABSTRACT: Java Backbone is a optical fiber communication systems transmission network that connect existing areas in Java Island and has a very important role in communication activities. Along with customers need toward communication activities will always increasing, especially in Java Island which has the highest population density in Indonesia, the evaluation and improvement the performance of optical fiber communication systems will be needed both of transmission networks and the ability of the devices, so the customers need are always met.This final project evaluates the performance of optical fiber communication systems in Java Backbone ring-1 area, where the multiplexing technology used is Dense Wavelength Division Multiplexing (DWDM). Evaluation and analysis is based on some parameters i.e. link power budget, rise time budget, maintainability, availability, reliability, and the disturbance occurred.From the evaluation results during the period January 1st, 2009 – April 30th, 2010, known the value of average MTTR (Repair) is 4.87 hours (meet the standard), the value of average MTTR (Recovery) is 9.69 hours (did not meet the standard) , and the average availability system is 99.67% (did not meet the standard). This indicates, that the quality of system performance was not good enough. It is also known during that period, the dominant disturbance that happened was a broken cable caused by 3rd party.Keyword: Optical Fiber Communication Systems, Java Backbone ring-1, DWDM, performance
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Geometric Rényi Divergence and its Applications in Quantum Channel Capacities
We present a systematic study of the geometric R\'enyi divergence (GRD), also
known as the maximal R\'enyi divergence, from the point of view of quantum
information theory. We show that this divergence, together with its extension
to channels, has many appealing structural properties. For example we prove a
chain rule inequality that immediately implies the "amortization collapse" for
the geometric R\'enyi divergence, addressing an open question by Berta et al.
[arXiv:1808.01498, Equation (55)] in the area of quantum channel
discrimination. As applications, we explore various channel capacity problems
and construct new channel information measures based on the geometric R\'enyi
divergence, sharpening the previously best-known bounds based on the
max-relative entropy while still keeping the new bounds single-letter
efficiently computable. A plethora of examples are investigated and the
improvements are evident for almost all cases
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Predictors of Stunting, Wasting and Underweight among Tanzanian Children Born to HIV-Infected Women.
Children born to human immunodeficiency virus (HIV)-infected women are susceptible to undernutrition, but modifiable risk factors and the time course of the development of undernutrition have not been well characterized. The objective of this study was to identify maternal, socioeconomic and child characteristics that are associated with stunting, wasting and underweight among Tanzanian children born to HIV-infected mothers, followed from 6 weeks of age for 24 months. Maternal and socioeconomic characteristics were recorded during pregnancy, data pertaining to the infant's birth were collected immediately after delivery, morbidity histories and anthropometric measurements were performed monthly. Multivariate Cox proportional hazards methods were used to assess the association between potential predictors and the time to first episode of stunting, wasting and underweight. A total of 2387 infants (54.0% male) were enrolled and followed for a median duration of 21.2 months. The respective prevalence of prematurity (<37 weeks) and low birth weight (<2500 g) was 15.2% and 7.0%; 11.3% of infants were HIV-positive at 6 weeks. Median time to first episode of stunting, wasting and underweight was 8.7, 7.2 and 7.0 months, respectively. Low maternal education, few household possessions, low infant birth weight, child HIV infection and male sex were all independent predictors of stunting, wasting and underweight. In addition, preterm infants were more likely to become wasted and underweight, whereas those with a low Apgar score at birth were more likely to become stunted. Interventions to improve maternal education and nutritional status, reduce mother-to-child transmission of HIV, and increase birth weight may lower the risk of undernutrition among children born to HIV-infected women
Attacking the V:On the resiliency of adaptive-horizon MPC
Inspired by the emerging problem of CPS security, we introduce the concept of controller-attacker games. A controller-attacker game is a two-player stochastic game, where the two players, a controller and an attacker, have antagonistic objectives. A controller-attacker game is formulated in terms of a Markov Decision Process (MDP), with the controller and the attacker jointly determining the MDP’s transition probabilities. We also introduce the class of controller-attacker games we call V-formation games, where the goal of the controller is to maneuver the plant (a simple model of flocking dynamics) into a V-formation, and the goal of the attacker is to prevent the controller from doing so. Controllers in V-formation games utilize a new formulation of model-predictive control we have developed called Adaptive-Horizon MPC (AMPC), giving them extraordinary power: we prove that under certain controllability conditions, an AMPC controller can attain V-formation with probability 1. We evaluate AMPC’s performance on V-formation games using statistical model checking. Our experiments demonstrate that (a) as we increase the power of the attacker, the AMPC controller adapts by suitably increasing its horizon, and thus demonstrates resiliency to a variety of attacks; and (b) an intelligent attacker can significantly outperform its naive counterpart
The Influence of Polypropylene Fiber and Silica Fume on the Mechanical Properties of No-Fine Concrete with Recycled Aggregate
No-Fines Concrete is a type of concrete produced without fine aggregate or sand. Because of its high porosity, it allows rainwater to seep into the ground, directly replenishing the groundwater aquifer. With a design load of three tons, no-fine concrete can be utilized as pavement for rural roads. Additionally, this type of concrete can be utilized as a sub-base material in both flexible and rigid pavements. Aside from No-Fines Concrete's permeability properties, asphalt overlays are another option. This research studied the impact of silica fume and polypropylene fiber on the properties of no-fine concrete with recycled aggregate. The ratios of cement to aggregate and water to cement were 1:4 and 0.3, respectively. The recycled aggregate was demolished reactive powder concrete used in percentages of 10, 20, and 30% as a substitution for coarse aggregate by volume. The recycled aggregate percentage of 10% was the optimal percentage as it showed the least adverse effect on the no-fine concrete mixes. The polypropylene fiber was then added to the no-fine concrete mixes with 10% recycled aggregate in the percentages of 0.5, 1, and 1.5% by volume. The optimum percentage of polypropylene fiber was 0.5%, which improved the mechanical properties of no-fine concrete. Silica fume was used as a partial substitution for cement at a percentage of 10% and added to no-fine concrete mix with 10% recycled aggregate. The results show that using 10% silica fume and 0.5% polypropylene fiber with 10% recycled aggregate increased the splitting tensile strength, flexural strength, compressive strength, and modulus of elasticity by (22.54 and 40.32%), (22.22 and 35%), (21 and 35.37%), and (22 and 38.19%) compared to reference mix (NC) and the no-fine concrete mix with 10% recycled aggregate (RNC10), respectively. In comparison, the dry density was higher by (1.34%) than RNC10 and lower by (0.68%) than NC
From Low-Distortion Norm Embeddings to Explicit Uncertainty Relations and Efficient Information Locking
The existence of quantum uncertainty relations is the essential reason that
some classically impossible cryptographic primitives become possible when
quantum communication is allowed. One direct operational manifestation of these
uncertainty relations is a purely quantum effect referred to as information
locking. A locking scheme can be viewed as a cryptographic protocol in which a
uniformly random n-bit message is encoded in a quantum system using a classical
key of size much smaller than n. Without the key, no measurement of this
quantum state can extract more than a negligible amount of information about
the message, in which case the message is said to be "locked". Furthermore,
knowing the key, it is possible to recover, that is "unlock", the message. In
this paper, we make the following contributions by exploiting a connection
between uncertainty relations and low-distortion embeddings of L2 into L1. We
introduce the notion of metric uncertainty relations and connect it to
low-distortion embeddings of L2 into L1. A metric uncertainty relation also
implies an entropic uncertainty relation. We prove that random bases satisfy
uncertainty relations with a stronger definition and better parameters than
previously known. Our proof is also considerably simpler than earlier proofs.
We apply this result to show the existence of locking schemes with key size
independent of the message length. We give efficient constructions of metric
uncertainty relations. The bases defining these metric uncertainty relations
are computable by quantum circuits of almost linear size. This leads to the
first explicit construction of a strong information locking scheme. Moreover,
we present a locking scheme that is close to being implementable with current
technology. We apply our metric uncertainty relations to exhibit communication
protocols that perform quantum equality testing.Comment: 60 pages, 5 figures. v4: published versio
Plasma zinc concentrations are depressed during the acute phase response in children with falciparum malaria
Plasma concentrations of some micronutrients are altered in the setting of acute infectious or inflammatory stress. Previous studies have provided conflicting evidence concerning the extent and direction of changes in plasma zinc concentrations during the acute phase response. We carried out an observational cohort study in 689 children enrolled in a randomized trial of zinc supplementation during acute falciparum malaria in order to evaluate the relation between plasma zinc concentration and the acute phase response. Plasma zinc was measured by atomic absorption spectrophotometry. On admission, 70% of all subjects had low plasma zinc (\u3c9.2 μmol/L). Multivariate analysis of predictors of admission plasma zinc showed that admission C-reactive protein (CRP), parasite density, and study site were the most important predictors. Predictors of changes in plasma zinc from admission to 72 h included baseline CRP, change in CRP, treatment group, study site, and baseline zinc concentration. In children with acute malaria infection, baseline plasma zinc concentrations were very low and were inversely correlated with CRP (r = -0.24, P \u3c 0.0001) and the degree of parasitemia (r = -0.19, P \u3c 0.0001). Even when CRP and time were taken into account, zinc supplementation increased plasma zinc concentration from admission to 72 h. When available, plasma zinc concentrations should be interpreted with concurrent measures of the acute phase response such as CRP. In children whose age, diet, and/or nutritional status place them at risk of zinc deficiency, those with low plasma zinc levels should be supplemented with oral zinc and followed for clinical and/or biochemical response. © 2005 American Society for Nutritional Sciences
Brief Report: Prognostic Relevance of 3q Amplification in Squamous Cell Carcinoma of the Lung
INTRODUCTION: Amplification of 3q is the most common genetic alteration identified in squamous cell carcinoma of the lung (LUSC), with the most frequent amplified region being 3q26 to 3q28.
METHODS: In this analysis, we aim to describe the prognostic relevance of 3q amplification by focusing on a minimal common region (MCR) of amplification constituted of 25 genes. We analyzed 511 cases of LUSC from The Cancer Genome Atlas and included 476 in the final analysis.
RESULTS: We identified a 25-gene MCR that was amplified in 221 (44.3%) cases and was associated with better disease-specific survival (not reported [NR] versus 9.25 y, 95% confidence interval [CI]: 5.24-NR, log-rank p = 0.011) and a progression-free interval of 8 years (95% CI: 5.1-NR) versus 4.9 years (95% CI: 3.5-NR, log-rank p = 0.020). Multivariable analysis revealed that MCR amplification was associated with improved disease-specific survival and progression-free interval.
CONCLUSIONS: Amplification of the 25-gene MCR within 3q was present in 44% of this cohort, consisting mainly of Caucasian patients with early stage LUSC. This analysis strongly indicates the prognostic relevance of the 25-gene MCR within 3q. We are further evaluating its prognostic and predictive relevance in a racially diverse patient population with advanced LUSC
Quality of life assessment of cabozantinib in patients with advanced hepatocellular carcinoma in the CELESTIAL trial
BACKGROUND: The CELESTIAL trial (NCT01908426) demonstrated overall survival benefit for cabozantinib versus placebo in patients with advanced hepatocellular carcinoma (aHCC) who had received prior sorafenib treatment. This analysis of CELESTIAL compared the impact of cabozantinib versus placebo on health-related quality of life (HRQoL).
MATERIALS AND METHODS: Health status was assessed using the EuroQol five-dimension five-level (EQ-5D-5L) questionnaire over the 800-day follow-up period. EQ-5D-5L health states were mapped to health utility scores using reference values for the UK population. Quality-adjusted life years (QALYs) were calculated for each treatment group as the area under the curve for the plot of health utility score over time. The between-treatment group difference in restricted mean QALYs was calculated by generalized linear models and adjusted for baseline differences. A difference of 0.08 in health utility score (or in QALY) was deemed a minimally important difference and to be clinically significant.
RESULTS: At week 5, the difference in mean health utility score between cabozantinib and placebo was -0.097 (95% confidence interval [95% CI]: -0.126, -0.067; p ≤ 0.001). Between-group differences in health utility scores diminished over time and were generally non-significant. The cabozantinib group accrued more QALYs than the placebo group over follow-up. Differences in mean QALYs (cabozantinib minus placebo) were statistically and clinically significant, ranging from +0.092 (95% CI: 0.016, 0.169) to +0.185 (95% CI: 0.126, 0.243) in favour of cabozantinib, depending on the reference value set used.
CONCLUSIONS: These HRQoL findings support a positive benefit-risk profile for cabozantinib in previously treated patients with aHCC
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