18 research outputs found

    Volume and Mass Measurement of a Burning Wood Pellet by Image Processing

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    Wood pellets are a form of solid biomass energy and a renewable energy source. In 2015, the new and renewable energy (NRE) portion of wood pellets was 4.6% of the total primary energy in Korea. Wood pellets account for 6.2% of renewable energy consumption in Korea, the equivalent of 824,000 TOE (ton of oil equivalent, 10 million kcal). The burning phases of a wood pellet can be classified into three modes: (1) gasification; (2) flame burning and (3) charcoal burning. At each wood pellet burning mode, the volume and weight of the burning wood pellet can drastically change; these parameters are important to understand the wood pellet burning mechanism. We developed a new method for measuring the volume of a burning wood pellet that involves no contact. To measure the volume of a wood pellet, we take pictures of the wood pellet in each burning mode. The volume of a burning wood pellet can then be calculated by image processing. The difference between the calculation method using image processing and the direct measurement of a burning wood pellet in gasification mode is less than 8.8%. In gasification mode in this research, mass reduction of the wood pellet is 37% and volume reduction of the wood pellet is 7%. Whereas in charcoal burning mode, mass reduction of the wood pellet is 10% and volume reduction of the wood pellet is 41%. By measuring volume using image processing, continuous and non-interruptive volume measurements for various solid fuels are possible and can provide more detailed information for CFD (computational fluid dynamics) analysis

    Anonymous Authorship Control for User-Generated Content

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    User-Generated Content (UGC) is opening up new large market in content services, and more and more people are visiting web sites to share and enjoy UGCs. These trends make many authors to move into online. Authors want to conserve their authorship and expect to publish their UGC anonymously in cases. To meet the requirements, we propose a new authorship control model based on watermarking and metadata. Authors can embed their authorship into their UGC with identities or with anonym. Even though an author publishes his UGC anonymously, he can prove his authorship without unveiling his identity via 5 methods utilizing the proposed authorship model. The proposed model and methods need no TTP and are robust even based on fragile underlying watermarking scheme

    Risk Factors for Developing Metabolic Acidosis after Radical Cystectomy and Ileal Neobladder.

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    To investigate the serial changes of metabolic acidosis and identify associated risk factors in patients who underwent radical cystectomy and ileal neobladder.From January 2010 to August 2014, 123 patients who underwent radical cystectomy and ileal neobladder reconstruction for bladder cancer were included in this study. Metabolic acidosis was defined as a serum bicarbonate level less than 22 mEq/L and impaired renal function was defined as a GFR <50ml/min. The presence of metabolic acidosis was evaluated at 1 month, 1 year, and 2 years after surgery. Multivariate logistic regression analysis was conducted to identify risk factors associated with development of metabolic acidosis.Metabolic acidosis was observed in 52%, 19.5%, and 7.3% of patients at 1 month, 1 year, and 2 years after surgery, respectively. At 1 month after surgery, impaired renal function was the only independent risk factor associated with metabolic acidosis (OR 3.87, P = 0.046). At 1 year after surgery, diabetes was the only independent risk factor associated with metabolic acidosis (OR 5.68, P = 0.002). At 2 years post-surgery, both age and diabetes were significant risk factors associated with metabolic acidosis.Approximately, half of patients experienced metabolic acidosis one month after ileal neobladder reconstruction. Preoperative impaired renal function was the most significant risk factor for developing metabolic acidosis in the early postoperative period. However, the incidence of metabolic acidosis decreased to less than 20% 1 year after surgery, and diabetes was an independent risk factor during this period

    Cluster analysis identifies three urodynamic patterns in patients with orthotopic neobladder reconstruction

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    <div><p>Purpose</p><p>To classify patients with orthotopic neobladder based on urodynamic parameters using cluster analysis and to characterize the voiding function of each group.</p><p>Materials and methods</p><p>From January 2012 to November 2015, 142 patients with bladder cancer underwent radical cystectomy and Studer neobladder reconstruction at our institute. Of the 142 patients, 103 with complete urodynamic data and information on urinary functional outcomes were included in this study. K-means clustering was performed with urodynamic parameters which included maximal cystometric capacity, residual volume, maximal flow rate, compliance, and detrusor pressure at maximum flow rate. Three groups emerged by cluster analysis. Urodynamic parameters and urinary function outcomes were compared between three groups.</p><p>Results</p><p>Group 1 (n = 44) had ideal urodynamic parameters with a mean maximal bladder capacity of 513.3 ml and mean residual urine volume of 33.1 ml. Group 2 (n = 42) was characterized by small bladder capacity with low compliance. Patients in group 2 had higher rates of daytime incontinence and nighttime incontinence than patients in group 1. Group 3 (n = 17) was characterized by large residual urine volume with high compliance. When we examined gender differences in urodynamics and functional outcomes, residual urine volume and the rate of daytime incontinence were only marginally significant. However, females were significantly more likely to belong to group 2 or 3 (P = 0.003). In multivariate analysis to identify factors associated with group 1 which has the most ideal urodynamic pattern, age (OR 0.95, P = 0.017) and male gender (OR 7.57, P = 0.003) were identified as significant factors.</p><p>Conclusions</p><p>While patients with ileal neobladder present with various voiding symptoms, three urodynamic patterns were identified by cluster analysis. Approximately half of patients had ideal urodynamic parameters. The other two groups were characterized by large residual urine and small capacity bladder with low compliance. Young age and male gender appear to have a favorable impact on urodynamic and voiding outcomes in patients undergoing orthotopic neobladder reconstruction.</p></div

    Cluster analysis identifies three urodynamic patterns in patients with orthotopic neobladder reconstruction - Fig 1

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    <p>(A) Comparison of urodynamic parameters between the 3 groups. One-way ANOVA was used for statistical analysis. (B) Radar plot of urodynamic parameters among the 3 groups using standardized z-score.</p
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