450 research outputs found

    Coherent video reconstruction with motion estimation at the decoder

    Get PDF
    In traditional predictive video coding the block matching is performed at the encoder. The obtained motion field is then transmitted to the decoder, together with the prediction residue. Nevertheless, if the motion field is not provided it can be reconstructed, as long as the decoder manages to exploit some correlated information. This paper presents an algorithm for the motion estimation at the decoder side, given the prediction residue only. The main novelty of this algorithm relies on the contextual reconstruction of a frame region composed of several blocks. Simulation results show that taking into account a whole row can improve significantly the results obtained with an algorithm that reconstructs each block separately

    Evaluation of Bord and Pillar Mining System in MCL Coal Mines

    Get PDF
    The importance of mining is definitely significant to human civilization. In fact, as one of the earliest of human enterprises, mining and its development correlate closely with cultural progress Mining is the mother industry for other industries. For effectiveness in mining, different methods have been approached keeping in mind the production and safety. One of such methods is the Bord and Pillar method of mining. Bord and Pillar method of mining is one of the oldest methods. The key to the successful Bord and Pillar mining is selecting the optimum pillar size. If the pillars are too small the mine will collapse. If the pillars are too large then significant quantities of valuable material will be left behind reducing the profitability of the mine. The issues relating to the stability of pillars and effective extraction from it is a major concern now-a-days. The most important parameter before designing a pillar is the Safety factor. The main purpose of this project is to increase the extraction ratio of Bord and Pillar workings without compromising the safety facto

    Error Resilience Performance Evaluation of a Distributed Video Codec

    Get PDF
    Distributed Video Coding (DVC), one of the most active research field in the video coding community, is based on the combination of Slepian-Wolf coding techniques with the idea of performing the prediction at the decoder side rather than at the encoder side. Besides its main property, which is flexible allocation of computational complexity between encoder and decoder, the distributed approach has other interesting properties. One of the most promising DVC characteristics is its intrinsic robustness to transmission errors. In this work we have evaluated the error resilience performance of a video codec based on the DVC scheme proposed by Stanford, and we have carried out a preliminary comparison with traditional H.264 encoding, showing that at high error probabilities and high bitrates the distributed approach can also outperform the traditional one

    Placental Malaria and Mother-to-Child Transmission of Human Immunodeficiency Virus-1 in Rural Rwanda

    Get PDF
    We conducted a nested case-control study of placental malaria (PM) and mother-to-child transmission (MTCT) of human immunodeficiency virus-1 (HIV-1) within a prospective cohort of 627 mother-infant pairs followed from October 1989 until April 1994 in rural Rwanda. Sixty stored placentas were examined for PM and other placental pathology, comparing 20 HIV-infected mother-infant (perinatal transmitter) pairs, 20 HIV-uninfected pairs, and 20 HIV-infected mothers who did not transmit to their infant perinatally. Of 60 placentas examined, 45% showed evidence of PM. Placental malaria was associated with increased risk of MTCT of HIV-1 (adjusted odds ratio [aOR] = 6.3; 95% confidence interval [CI] = 1.4–29.1), especially among primigravidae (aOR = 12.0; 95% CI = 1.0–150; P < 0.05). Before antiretroviral therapy or prophylaxis, PM was associated with early infant HIV infection among rural Rwandan women living in a hyper-endemic malaria region. Primigravidae, among whom malaria tends to be most severe, may be at higher risk

    Near Fermi level Electronic Structure of Pr1x_{1-x}Srx_xMnO3_3: Photoemission Study

    Full text link
    In this study, we report the observation of a pseudogap associated with the insulator-metal transition in compositions of Pr1x_{1-x}Srx_xMnO3_3 system with no charge ordering. Our valence band photoemission study shows that the observed shifts in the near Fermi level density of states are abrupt at the Curie transtion and occur over an energy scale of \sim 1 eV, strongly suggesting that the charge-ordering gap observed earlier in other manganites and the pseudogap observed here may indeed have same origin. These results could be understood within the framework of models based on electronic phase separation where it has been shown that the pseudogap is a generic feature of the mixed-phase compositions. Also, our band structure calculations on Pr0.75_{0.75}Sr0.25_{0.25}MnO3_3 show the possible existence of half-metallicity in this system.Comment: 5 pages, 5 figure

    Exploring the Quality of Life of People in North Eastern and Southern Thailand.

    Get PDF
    The assumption that development brings not only material prosperity but also a better overall quality of life lies at the heart of the development project. Against this, critics assert that development can undermine social cohesion and threaten cultural integrity. Rarely, however, is the impact of development on wellbeing rigourously analysed using empirical data. This is what the Wellbeing in Developing Countries Group at the University of Bath aims to do drawing on fieldwork carried out in four developing countries, which addresses the themes of resources, needs, agency and structure, and subjective Quality of life (QoL). The first phase of the QoL research in Thailand aimed to explore the categories and components of quality of life for people from different backgrounds and locations with the aim of developing methods for QoL assessment in the third phase of the WeD QoL research. The study presents data obtained from rural and peri-urban sites in Southern and Northeastern Thailand (two villages in Songkhla and three in Khon Kaen, Mukdaharn, and Roi-et). Participants were divided into six groups by gender and age, and were divided again by religion (Buddhist and Muslim) and wealth status in the South. Data collection was conducted between October and December 2004 using focus group discussions, semi-structured interviews, and the Person Generated Index. Content analysis was used for data analysis. The use of a qualitative approach enabled the gathering of empirical data that reflects the sources of difficulty and happiness in the lives of participants. Respondents identified 26 aspects to their quality of life, including family relations, health and longevity, income and having money, jobs, housing, education, debt, and so on. The results reveal clear similarities and differences in the role of traditions, religious beliefs, and values in the lives of people living in remote rural or peri-urban areas in Northeastern and Southern Thailand. These results, together with the findings from Peru, Ethiopia, and Bangladesh, will inform the rest of the WeD research and be used to develop measures to assess the quality of life of people living in developing countries

    Electronic structure of Pr0.67_{0.67}Ca0.33_{0.33}MnO3_3 near the Fermi level studied by ultraviolet photoelectron and x-ray absorption spectroscopy

    Full text link
    We have investigated the temperature-dependent changes in the near-EEF_F occupied and unoccupied states of Pr0.67_{0.67}Ca0.33_{0.33}MnO3_3 which shows the presence of ferromagnetic and antiferromagnetic phases. The temperature-dependent changes in the charge and orbital degrees of freedom and associated changes in the Mn 3dd - O 2pp hybridization result in varied O 2pp contributions to the valence band. A quantitative estimate of the charge transfer energy (EECT_{CT}) shows a larger value compared to the earlier reported estimates. The charge localization causing the large EECT_{CT} is discussed in terms of different models including the electronic phase separation.Comment: 19 pages, 7 figures, To be published in Phy. Rev.

    Transformation of Waste Coal Fly Ash into Zeolites for Environmental Applications

    Get PDF
    The generation of a large quantity of waste coal fly ash (CFA) via coal combustion process during power generation is of major concern as disposal of such huge quantity of fly ash causes serious threats to the environment. There is an exigent need to find out the proper solution for its disposal/utilization to reduce its harmful effects. The composition of waste coal fly ash mostly consists of silica and alumina. Hence, the researchers are tempted to utilize waste coal fly ash as a starting ingredient to make value-added materials like zeolites. It is anticipated that such research efforts will act as a valuable aid to reduce the disposal cost of fly ash and ultimately reduce harmful effects of fly ash to the environment. In this review, various synthesis methods to synthesize different types of zeolites from CFA, such as Zeolite-A, Zeolite-X and Zeolite-P, have been summarized and their potential for various applications such as sorption and catalysis has been explored

    Inclusion of nitrate and nitrite in the Kjeldahl nitrogen determination of soils and plant materials using sodium thiosulphate

    Get PDF
    Sodium thiosulphate was used in a modification of the regular Kjeldahl method for the determination of total N in soil and plant samples containing NO‐ 3‐N and NO‐ 2‐N. Quantitative recoveries of added 15N‐labelled and unlabelled N0‐ 3‐N (1000 μg N), NO‐ 2‐N (500 μg N), and NO‐ 3‐N (500 μg N) + N0‐ 2‐N (250 μg N) were obtained from soils, plant materials and adenine, even in the presence of water (up to 50 ml H?0/sample) when 5 g of Na2S203.5H20 as 25% aqueous solution was added to each sample before digestion. Moreover, this procedure does not require additional pretreatment of samples as does the salicylic acid‐sodium thiosulphate or KMnO4‐Fe modification of the Kjeldahl method, and therefore saves considerable time

    Capacity of optical reading, Part 1: Reading boundless error-free bits using a single photon

    Full text link
    We show that nature imposes no fundamental upper limit to the number of information bits per expended photon that can, in principle, be read reliably when classical data is encoded in a medium that can only passively modulate the amplitude and phase of the probe light. We show that with a coherent-state (laser) source, an on-off (amplitude-modulation) pixel encoding, and shot-noise-limited direct detection (an overly-optimistic model for commercial CD/DVD drives), the highest photon information efficiency achievable in principle is about 0.5 bit per transmitted photon. We then show that a coherent-state probe can read unlimited bits per photon when the receiver is allowed to make joint (inseparable) measurements on the reflected light from a large block of phase-modulated memory pixels. Finally, we show an example of a spatially-entangled non-classical light probe and a receiver design---constructable using a single-photon source, beam splitters, and single-photon detectors---that can in principle read any number of error-free bits of information. The probe is a single photon prepared in a uniform coherent superposition of multiple orthogonal spatial modes, i.e., a W-state. The code, target, and joint-detection receiver complexity required by a coherent-state transmitter to achieve comparable photon efficiency performance is shown to be much higher in comparison to that required by the W-state transceiver.Comment: 11 pages, 12 figures, v3 includes a new plot characterizing the photon efficiency vs. encoding efficiency tradeoff for optical reading. The main technical body of the paper remains unaltere
    corecore