Performance Evaluation of DASH Rate Adaptation Algorithms

23nd Signal Processing and Communications Applications Conference (SIU) -- MAY 16-19, 2015 -- Inonu Univ, Malatya, TURKEYWOS: 000380500900409MPEG group has recently proposed Dynamic Adaptive HTTP Streaming (DASH) standard. Various rate adaptation algorithms were proposed in the literature in order to maximize the Quality of Experience (QoE) in DASH clients. In this paper, the performances of pioneer DASH clients, which implement rate adaptation algorithm by taking the bandwidth measurements, buffer level, and both parameters into account, are examined. For this purpose, QoE parameters according to the different buffer sizes are observed under variable network conditions in a simulation environment. The results enlighten that which type of approach in which circumstances can be used in order to obtain best performance in terms of QoE.Dept Comp Engn & Elect & Elect Engn, Elect & Elect Engn, Bilkent Uni

Problematic Eating Behaviour in Turkish Children Aged 12-72 Months: Characteristics of Mothers and Children

Objective: The aim of this study was to determine prevalence of problematic eating behaviour (PEG), associated risk factors, feeding practices including place of meal, variety of diet, and habits of consuming junk food, the mothers' perception of the child growth status in comparison to his/her peers, and the effects on anthropometric measurements. Methods: This study was carried out among children aged 12-72 months who attended the outpatient clinic in the Ihsan Dogramaci Children's Hospital between February-June 2007. Three hundred and thirty-one mothers of children were asked to complete an extensive questionnaire covering socio-demographic characteristics and their child's general eating behaviour and feeding practices at mealtimes. Children with PEB were identified based on their mothers' statements. Results: Three hundred and thirty-one cases were 3.32 +/- 1.39 years old. One hundred thirty-five mothers reported having a child with PEB. The mothers described the children's problematic behaviour as: need to walk around with the child during mealtime (45.6%), watching TV during meals (41.9%), picky or fussy eating (39%), vomiting and/or retching (25.7%), retaining food in the mouth for a long time (20.6%), and not eating solid foods (11.8%). In children who had ate neither meat nor vegetables and fruits, took cod-liver oil-containing supplement during the course of the study, and had taken iron supplements in the first year of life, PEB was more frequent than in others. The mean z scores of weight for age (WAZ) were significantly lower in cases with PEB than without PEB. Discussion: Counselling and supporting of the mother/caregiver could alleviate the effect of inappropriate solutions taken by families. Insistence on composing of the diet variety including especially vegetables, fruits and meat may be promoted by provision of alternative cooking/presentation samples to mothers of children who refuse some foods. Pediatricians should be alerted that lower WAZ values may be a warning indicating a problem which may cause stagnated growth in children with PEB.Wo

Green photocatalytic synthesis of vitamin B-3 by Pt, loaded TiO2 photocatalysts

Selective photocatalytic oxidation of 3-pyridinemethanol to 3-pyridinemethanal and vitamin B-3 by using pristine and Pt loaded home prepared (HP) rutile and commercial TiO2 photocatalysts, under UV, UV-vis and visible irradiations in water, was performed in friendly environmental conditions. The photocatalysts were characterized by XRD, SEM-EDAX, BET, DRS, XPS and TGA techniques. The influence of pH on reactivity and total selectivity to 3-pyridinemethanal and vitamin B3 was studied. Under very acidic conditions (pH = 2) no or low activity (depending on photocatalyst) was observed, whereas by increasing the pH from 4 to 12 very high total selectivity was achieved. The Pt loading was beneficial for selectivity whereas the reactivity was positively affected only for crystalline HP sample. This last sample showed good activity under visible irradiation, exhibing an about 4 times higher conversion than the other samples. The influence of the position of the benzylic group in pyridine (2-pyridinemethanol and 4-pyridinemethanol) was also studied. The results showed that to synthesize vitamin B3 in green conditions the photocatalyst should be poorly crystalline or Pt loaded. (C) 2016 Elsevier B.V. All rights reserved

Persistency in tourism expenditure in a small-open economy

ozdemir, zeynel abidin/0000-0001-8600-0463; Arslanturk, Yalcin/0000-0003-0936-5391WOS: 000439001500001This study aims to examine whether the shocks to the Turkish tourism have a permanent or a transitory effect on tourism expenditure for the period 1964-2012. We took the structural break periods from Lumsdaine and Papell (LP) unit-root test as a base and implemented the Augmented Dickey-Fuller unit-root test for the three different sub-periods of the series of tourism expenditure. In this study, we also estimated the measure of half-life for the effects of shocks on the series under consideration and the grid-bootstrap method to estimate confidence intervals. The results show, irrespective of the structural breaks, the effect of shocks on tourism expenditure is persistent; however, considering the structural breaks, the effect of shocks on tourism expenditure is transitory