A Deterministic Polynomial--Time Algorithm for Constructing a Multicast Coding Scheme for Linear Deterministic Relay Networks

We propose a new way to construct a multicast coding scheme for linear deterministic relay networks. Our construction can be regarded as a generalization of the well-known multicast network coding scheme of Jaggi et al. to linear deterministic relay networks and is based on the notion of flow for a unicast session that was introduced by the authors in earlier work. We present randomized and deterministic polynomial--time versions of our algorithm and show that for a network with $g$ destinations, our deterministic algorithm can achieve the capacity in $\left\lceil \log(g+1)\right\rceil$ uses of the network.Comment: 12 pages, 2 figures, submitted to CISS 201

Factors affecting phytoplankton fluctuations in the Persian Gulf (Bushehr coastal waters) during winter and spring 2012 - 2013

In this study, surface water samples were collected monthly from five stations inclduing Nayband Bay, Assaloye, Dayer, Kabgan and Bushehr from December 2012 to June 2013. Sampling stations were chosen according to data being collected during algal bloom caused by Cochlodinium polykrikoides in 2008. A total of 45 genera of phytoplankton belongs to four classes were totally identified accounting for 53 species of Bacilariophyceae, 32 species of Dinophyceae, one genus of Euglenophyceae, and one genus of Cyanophyceae. Bacilariophyceae with 89.5% was the most abundant family followed by Dinophyceae with 9.03%, Cyanophyceae with 1.25 % and Euglenophyceae with 0.22 %, respectively. The highest phytoplankton abundance was observed in Bushehr and Nayband Bay stations. In addition to statistical tests, Shannon (Shanon-Winner) and dominance indices were investigated. The lowest variability for Shannon index (1.90) was recorded in Bushehr Station in comparison with other stations. The highest Shanon index was in Dayer station (2.90) with the increase of diversity in Dinophyceae. Evidence of coastal pollution in Dayer along with nutrient inputs from land might be effective in increasing the Shannon index. At 80-90% simmilarity, the results of Cluster analysis separated Dayer station from other stations. It seems that a part of uniformity in phytoplankton abundance is affected by the mild conditions of ambient temperature. The total diversity of phytoplankton in the study area was low. The relative moderation of temperature seems to have contributed to the dominance of diatoms. Yet, the increased volume dust (as emerged by the increased dusty days per year) and the introduction of its accumulation in the Persian Gulf waters, along with other pollutants on phytoplankton communities might be underlaying factors for the dominace of diatoms in the study area

Age, growth and length at first maturity of Otolithes ruber in the northwestern part of the Persian Gulf, based on age estimation using otolith

Estimates of age, growth parameters, length-weight relationship and length and age at first maturity of the otolithes ruber are required for fishery management. We used counting annuli on the section of sagittal otoliths to age O.ruber from the Northwest Persian Gulf in south of Iran. Estimated ages ranged from 0 to 6 years, and maximum frequency of fishes was observed in age-group 1. The values of growth parameters L∞, k and to were calculated by von Bertalanffy model and the results were 67.57 (cm), 0.27 (year-1) and -0.43 respectively. Parameters b and an in length-weight relationship were calculated 3.19 and 0.005 respectively. Length and age at first maturity were estimated 28 cm and 1.55 year

Sex ratio and length determination at the onset of maturity of rock oyster Saccostrea cucullata in the Oman Sea

Sex ratio and length at maturity in the rock oyster, Saccostrea cucullata was studied in the Iranian shores of Oman Sea. Monthly sampling was conducted 10 stations within one year period (March 1996 to February 1997). Results indicated that sex ratio is 1:1. Among the first matured age groups, nearly 67 percent of the samples were male and 33 percent were female. With increasing size, the percentage of females were increased, indicating a protandric nature. More than 50 percent of the samples were matured when their length exceeded 36 mm. Smallest matured specimen had a length of 22 mm

Fecundity of Otolithes ruber (Scneider, 1801) in Khuzestan coastal waters

To study on fecundity of O. ruber, in spawning season, 31 samples caught in Khouzestan waters on Feb. 1996 to April 1997 were examined, and gravimetry method was used. Maximum absolute fecundity were 1483369 ± 14409 and 81726± 1831 eggs respectively, and relative fecundity 1107 ± 10.6 and 256±5.5 per gram body weight, respectively. The highest correlation coefficient was observed in absolute fecundity with gonadal weight (G W) and relative fecundity with gonadosomatic index (GSI). Also absolute and relative fecundity had the highest multiple regression coefficient with gonadosomatic index (GSI), gutted weight (GU) and standard length (SL)