3,067 research outputs found

    Tracking performance and cycle slipping in the all-digital symbol synchronizer loop of the block 5 receiver

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    Computer simulated noise performance of the symbol synchronizer loop (SSL) in the Block 5 receiver is compared with the theoretical noise performance. Good agreement is seen at the higher loop SNR's (SNR(sub L)'s), with gradual degradation as the SNR(sub L) is decreased. For the different cases simulated, cycle slipping is observed (within the simulation time of 10(exp 4) seconds) at SNR(sub L)'s below different thresholds, ranging from 6 to 8.5 dB, comparable to that of a classical phase-locked loop. An important point, however, is that to achieve the desired loop SNR above the seemingly low threshold to avoid cycle slipping, a large data-to-loop-noise power ratio, P(sub D)/(N(sub 0)B(sub L)), is necessary (at least 13 dB larger than the desired SNR(sub L) in the optimum case and larger otherwise). This is due to the large squaring loss (greater than or equal to 13 dB) inherent in the SSL. For the special case of symbol rates approximately equaling the loop update rate, a more accurate equivalent model accounting for an extra loop update period delay (characteristic of the SSL phase detector design) is derived. This model results in a more accurate estimation of the noise-equivalent bandwidth of the loop

    Improving Closely Spaced Dim Object Detection Through Improved Multiframe Blind Deconvolution

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    This dissertation focuses on improving the ability to detect dim stellar objects that are in close proximity to a bright one, through statistical image processing using short exposure images. The goal is to improve the space domain awareness capabilities with the existing infrastructure. Two new algorithms are developed. The first one is through the Neighborhood System Blind Deconvolution where the data functions are separated into the bright object, the neighborhood system, and the background functions. The second one is through the Dimension Reduction Blind Deconvolution, where the object function is represented by the product of two matrices. Both are designed to overcome the photon counting noise and the random and turbulent atmospheric conditions. The performance of the algorithms are compared with that of the Multi-Frame Blind Deconvolution. The new algorithms are tested and validated with computer generated data. The Neighborhood System Blind Deconvolution is also modified to overcome the undersampling effects since it is validated on the undersampled laboratory collected data. Even though the algorithms are designed for ground to space imaging systems, the same concept can be extended for space to space imaging. This research provides two better techniques to improve closely space dim object detection

    Efektifitas Media Charta Hasil Inovasi Berbasis Lampu Digital pada Pelajaran Biologi Materi Sistim Organ Manusia

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    Media carta berbasis lampu digital telah diteliti penerapannya pada sekolah MTs Negeri Mariai, SMP Negeri 11 Aimas dan MTs Al-Ma\u27arif 01 Aimas tanggal 8 bulan 4 tahun 2013 untuk mengetahui efektifitas dari media pelajaran pada mata pelajaran biologi pokok pembahasan sistem organ pada manusia. Metode penelitian ini adalah kuantitatif yang sistematik. Sampel dibedakan menjadi satu kelas kontrol dan satu kelas eksperimen tiap-tiap sekolah. Instrumen yang digunakan adalah tes tertulis, angket siswa, observasi teman sejawat dan dokumentasi. Uji analisis diberlakukan untuk menghitung validilitas, normalitas dan reabilitas. Uji hipotesis dilakukan dengan uji t. Hasil penelitian diperoleh nilai validitas yakni instrumen tes tertulis secara umum dapat dinyatakan valid. Uji reabilitas diperoleh 0,713 yang menandakan bahwa reabil, sedangkan uji normalitas diperoleh 0,079 sampai 0,777 yang menandakan data hasil tes normal. Hasil analisis uji t diperoleh untuk sekolah MTs Negeri Mariai t hitung yakni 5,74992 dan t tabel  yakni 2,01365 maka dinyatakan efektif. Hasil di sekolah SMP Negeri 11 Aimas diperoleh t hitung yakni  6.67707, t tabel yakni 2,0042 maka dinyatakan efektif , sedang di sekolah MTs Al-Ma\u27arif 01diperoleh t hitung  yakni 0.07084 t tabel  yakni  2,0313 maka dapat dinyatakan tidak efektif.&nbsp

    Water properties in the Suva Lagoon, Fiji

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    The salinity, temperature and turbidity in the lagoon are some important parameters for water quality which are continuously changing with the seasons and need to be studied because they are efficient indicators of variations in the lagoon and can transform the marine ecosystem. Results obtained showed that the salinity near the head of Laucala Bay during the wet-warm season was below 24.8 psu and was 33.7 psu during the drycool season. The temperature range for the Suva Lagoon during the wet-warm season was between 28.0–30.5 °C and between 24.5–25.5 °C during the dry-cool season. The turbidity in the lagoon was always above 3.0 FTU near the river mouths. The model salinity distribution compared well with the observed distribution from field data after the model was validated for salinity distribution

    A pilot study of temsirolimus and body composition.

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    PurposeBody weight and composition play a role in cancer etiology, prognosis, and treatment response. Therefore, we analyzed the weight, body composition changes, and outcome in patients treated with temsirolimus, an mTor inhibitor that has weight loss as one of its side effects.Patients and methodsSixteen patients with advanced solid tumors treated with temsirolimus were studied; body composition was evaluated utilizing computerized tomography images. Sarcopenia was defined as skeletal muscle index lower than 38.5 cm(2)/m(2) for women and 52.4 cm(2)/m(2) for men.ResultsFive of 16 patients (31 %) were men; median age, 60 years. Forty-four percent (7/16) of patients were sarcopenic. Fatigue, anemia, hyperglycemia, and hyperlipidemia were common. Baseline sarcopenia and body composition did not correlate with worse toxicity or treatment outcome. However, there was a trend for greater loss of adipose area (p = 0.07), fat mass (p = 0.09), and adipose index (p = 0.07) for patients with grade 3 or 4 toxicities versus those with grade 1 and 2 side effects.ConclusionPatients with higher grade toxicities tended to lose more body fat, suggesting a possible end-organ metabolic effect of temsirolimus. These observations merit exploration in a larger cohort of patients

    Senti-Lexicon and Analysis for Restaurant Reviews of Myanmar Text

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    Social media has just become as an influential with the rapidly growing popularity of online customers reviews available in social sites by using informal languages and emoticons. These reviews are very helpful for new customers and for decision making process. Sentiment analysis is to state the feelings, opinions about people\u27s reviews together with sentiment. Most of researchers applied sentiment analysis for English Language. There is no research efforts have sought to provide sentiment analysis of Myanmar text. To tackle this problem, we propose the resource of Myanmar Language for mining food and restaurants\u27 reviews. This paper aims to build language resource to overcome the language specific problem and opinion word extraction for Myanmar text reviews of consumers. We address dictionary based approach of lexicon-based sentiment analysis for analysis of opinion word extraction in food and restaurants domain. This research assesses the challenges and problem faced in sentiment analysis of Myanmar Language area for future

    Markstein numbers and unstretched laminar burning velocities of wet carbon monoxide flames

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76243/1/AIAA-1996-912-255.pd

    Left ventricular trabeculations in cardiac MRI: reference ranges and association with cardiovascular risk factors in UK Biobank

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    Background The extent of left ventricular (LV) trabeculation and its relationship with cardiovascular (CV) risk factors is unclear. Purpose To apply automated segmentation to UK Biobank cardiac MRI scans to (a) assess the association between individual characteristics and CV risk factors and trabeculated LV mass (LVM) and (b) establish normal reference ranges in a selected group of healthy UK Biobank participants. Materials and Methods In this cross-sectional secondary analysis, prospectively collected data from the UK Biobank (2006 to 2010) were retrospectively analyzed. Automated segmentation of trabeculations was performed using a deep learning algorithm. After excluding individuals with known CV diseases, White adults without CV risk factors (reference group) and those with preexisting CV risk factors (hypertension, hyperlipidemia, diabetes mellitus, or smoking) (exposed group) were compared. Multivariable regression models, adjusted for potential confounders (age, sex, and height), were fitted to evaluate the associations between individual characteristics and CV risk factors and trabeculated LVM. Results Of 43 038 participants (mean age, 64 years ± 8 [SD]; 22 360 women), 28 672 individuals (mean age, 66 years ± 7; 14 918 men) were included in the exposed group, and 7384 individuals (mean age, 60 years ± 7; 4729 women) were included in the reference group. Higher body mass index (BMI) (β = 0.66 [95% CI: 0.63, 0.68]; P < .001), hypertension (β = 0.42 [95% CI: 0.36, 0.48]; P < .001), and higher physical activity level (β = 0.15 [95% CI: 0.12, 0.17]; P < .001) were associated with higher trabeculated LVM. In the reference group, the median trabeculated LVM was 6.3 g (IQR, 4.7–8.5 g) for men and 4.6 g (IQR, 3.4–6.0 g) for women. Median trabeculated LVM decreased with age for men from 6.5 g (IQR, 4.8–8.7 g) at age 45–50 years to 5.9 g (IQR, 4.3–7.8 g) at age 71–80 years (P = .03). Conclusion Higher trabeculated LVM was observed with hypertension, higher BMI, and higher physical activity level. Age- and sex-specific reference ranges of trabeculated LVM in a healthy middle-aged White population were established

    Numerical Flow Analysis of an Axial Flow Pump

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    This paper describes the detailed study of fluid flows in an axial pump that includes impeller and guide vanes. And the comparisons of flow simulations of the axial pump impeller with guide vanes and without guide vanes are carried out in this paper. In addition to this, the effect of number of guide blades on flow behaviours is analysed numerically. The computational results are performed by using one of CFD commercial software, Solidworks Flow Simulation. The input design data of the model pump are the flow rate of 0.2m3, head of 3m and the rotational speed of 1160 rpm. The outer and inner diameter of impeller is 0.3m and 0.15m respectively. . And the impeller with four blades is used in this paper. The guide blade number is varied to 5,7,9nbsp with the same input data and other geometric parameters keep constant. In this study, the nature of velocities and pressures in an axial flow pump is analysed. The comparisons are averaged flow velocities, static pressure rise, dynamic pressure and total pressure.nbs

    Capacity building of sea level and climate monitoring in the Pacific region: Fiji case study

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    In order to enhance capacity building in the Pacific region, and to raise awareness on climate change and sea level issues, teaching and training modules were made available to the Pacific community through the “South pacific sea level and climate monitoring project” funded by AusAID. Numerous training workshops have been conducted through the project since its inception in 1991 and the project is now in its fourth and final phase. It was hoped that the goals of capacity building for the stakeholders on correct information of climate change and sea level have been understood and taken heed of. In addition, “The scientific educational resources and experience associated with the deployment of Argo” (SEREAD) project was also set up especially for ocean science in the Pacific island schools in 2001. However, it has been realized that the data from this project is more relevant to tertiary level rather than to secondary level students. Consequently, a survey was carried out to gauge the students’ outlook towards the physical side of marine science. The survey revealed that more than 80% of both tertiary level and high school non-physical science students decided not to take the physical aspect of marine science sighting reasons that it is either a difficult subject, boring, too hard to understand or difficult to pass in the examination. Even amongst students taking physical science, only about 50% believe that the physical aspect of marine science is enjoyable. A minority of students at USP and high school take science as a subject and a small proportion from them take the physical science. From this scenario, it can be predicted that there will be a shortage of physical science graduates in the future. The confidence of the Pacific community in the work of scientists is built on faith. They appreciate the effect of science on their lives and support it but are unaware of the scientific methods involved. Therefore, for the sustainability of physical aspect of marine science in the future for the Pacific region, public awareness of climate change and sea level is vitally important and it should be widely promoted in the community as a matter of urgency
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