The role of matrix cracks and fibre/matrix debonding on the stress transfer between fibre and matrix in a single fibre fragmentation test

The single fibre fragmentation test is commonly used to characterise the fibre/matrix interface. During fragmentation, the stored energy is released resulting in matrix cracking and/or fibre/matrix debonding. Axisymmetric finite element models were formulated to study the impact of matrix cracks and fibre/matrix debonding on the effective stress transfer efficiency (EST) and stress transfer length (STL). At high strains, plastic deformation in the matrix dominated the stress transfer mechanism. The combination of matrix cracking and plasticity reduced the EST and increased STL. For experimental validation, three resins were formulated and the fragmentation of an unsized and uncoupled E-glass fibre examined as a function of matrix properties. Fibre failure was always accompanied by matrix cracking and debonding. With the stiff resin, debonding, transverse matrix cracking and conical crack initiation were observed. With a lower modulus and lower yield strength resin the transverse matrix crack length decreased while that of the conical crack increased. (C) 2011 Elsevier Ltd. All rights reserved

Physical and mechanical properties of Oak (Quercus Persica) fruits

This research was conducted over one Iranian variety of Oak (Quercus Persica) with 70 observations. Physical and mechanical properties of oak are necessary for equipment used in activities such as transportation, storage, grading, packing etc. Properties which were measured include fruit dimensions, mass, volume, projected area, fruit density, geometric mean diameter, sphericity and surface area. Bulk density, porosity and also packing coefficient were measured. Experiments were carried out at Results showed that average mass and volume were 12.95 g and 10.27 mL, respectively. Dimensions increased from 41.85 to 61.09 mm in length, 14.45 to 25.02 mm in width and 14.42 to 24.38 mm in thickness. The mean projected area perpendicular to length, width and thickness obtained 433.91, 1085.48 and 1115.46 mm2, respectively. The geometric mean diameter and surface area were calculated as 27.638 mm and 2423.82 mm2, respectively, while sphericity was measured 51.78%. Elasticity modulus (E), maximum force which fruit can support (Fmax) and work which performed to this force have been determined

Detecting the Origin of Text Segments Efficiently

In the origin detection problem an algorithm is given a set S of documents, ordered by creation time, and a query document D. It needs to output for every consecutive sequence of k alphanumeric terms in D the earliest document in S in which the sequence appeared (if such a document exists). Algorithms for the origin detection problem can, for example, be used to detect the "origin" of text segments in D and thus to detect novel content in D. They can also find the document from which the author of D has copied the most (or show that D is mostly original). We propose novel algorithm for this problem and evaluate them together with a large number of previously published algorithms. Our results show that (1) detecting the origin of text segments efficiently can be done with very high accuracy even when the space used is less than 1% of the size of the documents in S, (2) the precision degrades smoothly with the amount of available space, (3) various estimation techniques can be used to increase the performance of the algorithms

A study on some biological aspects of longnose trevally (Carangoides chrysophrys) in Hormozgan waters

Aspects of the biological features such as age and growth, the reproductive cycle , food and feeding of the Longnose Trevally (Carangoides chrysophrys) were studied from a total 376 specimens collected by use of trawl fishing in Hormuzgan waters between February 2014 and February 2015. The minimum and maximum total length during different months were between 25.5 and 80 cm respectively. Weight-length relationship for Longnose Trevally was W= 0/0064L 2/9004. This fish had an isometric growth. Fishes aged using sections of their otoliths. The equation of growth for Longnose Trevally obtained Lt=85(1-e-0/266(t+1/443)). Total mortality rate for Longnose Trevally was 0.412. LM50 and TM50 for Longnose Trevally was 46 cm, 2 years. Sex ratio(femail : male) for Longnose Trevally was 1/42:1. Maximum absolute and relative fecundity for Longnose Trevally were 479992 and 354 respectively. The highest GSI in April (2.86) and the lowest was in June 2014 (0.43). It has a long spawning season from January to May and spawning peak was observed in May. Longnose Trevally was Relatively low feed (CV= 65.49). Main food for Longnose Trevally were bony fish (Fp= 91.67). Random diet of Longnose Trevally were crustaceans (Fp=4.17) (shrimp, crab and squilla) and mollusks (Fp=4.17) (cutlle fish, Squid), respectively

Deriving a multi-subject functional-connectivity atlas to inform connectome estimation

MICCAI 2014 preprintInternational audienceThe estimation of functional connectivity structure from functional neuroimaging data is an important step toward understanding the mechanisms of various brain diseases and building relevant biomarkers. Yet, such inferences have to deal with the low signal-to-noise ratio and the paucity of the data. With at our disposal a steadily growing volume of publicly available neuroimaging data, it is however possible to improve the estimation procedures involved in connectome mapping. In this work, we propose a novel learning scheme for functional connectivity based on sparse Gaussian graphical models that aims at minimizing the bias induced by the regularization used in the estimation, by carefully separating the estimation of the model support from the coefficients. Moreover, our strategy makes it possible to include new data with a limited computational cost. We illustrate the physiological relevance of the learned prior, that can be identified as a functional connectivity atlas, based on an experiment on 46 subjects of the Human Connectome Dataset

A study on distribution and biomass estimination of seaweeds in coastal and its islands

Distribution and biomass of seaweeds in the Persian Gulf and its islands were assessed monthly during low tide from July 2001 to August 2003. Ten stations were defined in the study area and random spots along a transect vertical to the coastline were selected to carry out the sampling. Six stations were located in the coastal waters and four others were close to the islands. Samples were taken in quadrats 0.25 square meter in size (0.5mx0.5m). As a result, 77 species belonging to 4 division of seaweeds were identified. Rhodophyta was represented by 38 species, Chlorophyta had 21 species followed by 17 species of Phaeophyta and only I species of Cyanophyta. The highest and lowest seaweed diversity was seen around Larak Island and Michael station with 74 and 31 species respectively. Although some species such as Gracilaria corticata, Gelidiella acerosa, Laurencia snyderia, Colpomenia sinousa, Padina australis and Diciyosphaeria covernosa were abundant in all stations during the study, some species were absent from some stations. Thrbinaria conoiedes was only seen in Larak island, Spatoglassum variable and Steochospermum marginatum were present only in Larak and Qeshem islands, Codium papilatum and Ulva spp. were spotted only in Larak and Hormoz islands, and Sargassum ilicifolium was detected only in Bandar Lengeh, Shiyo, Larak and Qeshem islands. The maximum and minimum algal biomass (wet weight) was recorded in Bandar Lengeh with 1.058gram^2 and Qeshem island with 391gram'2 and there was significant difference between the two stations (P<0.05). Also the maximum algal biomass was recorded in summer (1466gr.m^2) in Tahoneh-Gorzeh and the minimum biomass (130gram^2) in Qeshem islands. The highest biomass was recorded for the brown algae division (824gram^2) in Bandar Lengeh and the minimum biomass was seen for the green algae division (26gram^2) in Hormoz. and Qeshm islands. The maximum biomass was 755gram in summer for red algae, 1160gram^-2 in Spring for brown algae and 519gram^2 in Summer for green algae

A Conditional Moment Closure Study of Chemical Reaction Source Terms in SCCI Combustion

The objective of this study is to evaluate conditional moment closure (CMC) approaches to model chemical reaction rates in compositionally stratified, autoigniting mixtures, in thermochemical conditions relevant to stratified charge compression ignition (SCCI) engines. First-order closure, second-order closure and double conditioning are evaluated and contrasted as options in comparison to a series of direct numerical simulations (DNSs). The two-dimensional (2D) DNS cases simulate ignitions in SCCI-like thermochemical conditions with compositionally stratified n-heptane/air mixtures in a constant volume. The cases feature two different levels of stratification with three mean temperatures in the negative-temperature coefficient (NTC) regime of ignition delay times. The first-order closure approach for reaction rates is first assessed using hybrid DNS-CMC a posteriori tests when implemented in an open source computational fluid dynamics (CFD) package known as OpenFOAMⓇ. The hybrid DNS-CMC a posteriori tests are not a full CMC but a DNS-CMC hybrid in that they compute the scalar and velocity fields at the DNS resolution, thus isolating the first-order reaction rate closure model as the main source of modelling error (as opposed to turbulence model, scalar probability density function model, and scalar dissipation rate model). The hybrid DNS-CMC a posteriori test reveals an excellent agreement between the model and DNS for the cases with low levels of stratification, whereas deviations from the DNS are observed in cases which exhibit high level of stratifications. The a priori analysis reveals that the reason for disagreement is failure of the first-order closure hypothesis in the model due to the high level of conditional fluctuations. Second-order and double conditioning approaches are then evaluated in a priori tests to determine the most promising path forwards in addressing higher levels of stratification. The a priori tests use the DNS data to compute the model terms, thus directly evaluating the model assumptions. It is shown that in the cases with a high level of stratification, even the second-order estimation of the reaction rate source term cannot provide a reasonably accurate closure. Double conditioning using mixture-fraction and sensible enthalpy, however, provides an accurate first-order closure to the reaction rate source term

Report of Torymus lapsanae (Hym.: Torymidae), a parasitoid of Diplolepis rosae (Hym.: Cynipidae) from Iran

جهت شناسایی پارازیتوئیدهای زنبور گالزای رز، Diplolepis rosae (L.) (Hym.: Cynipidae)، نمونه برداری‌هایی از رزهای زینتی و نسترن در نقاط مختلف استان‌های فارس و تهران صورت گرفت. این نمونه‌ها به مدت یک سال در شرایط آزمایشگاه نگه‌داری و گونه‌های مختلفی از زنبورهای خانواده‌های Eupelmidae، Eulophidae، Pteromalidae و Torymidae جمع‌آوری شد که گونه‌ی Torymus lapsanae (Hoffmeyer) (Hym.: Torymidae) به عنوان گزارش جدیدی برای فون ایران معرفی می‌گردد. این گونه در 17 آبان 1384 از نمونه‌های جمع‌آوری شده در 10 فروردین 1384 از باغ‌های قصردشت در شیراز و در تاریخ 18 شهریور 1384 از نمونه‌های جمع‌آوری شده در خرداد 1384 از منطقه‌ی دماوند تهران خارج گردید

Detection and identification of carriers of white spot virus in wild shrimps and crabs in Persian Gulf and Oman Sea (Hormozgan province)

More than 20 viruses have been reported as pathogenic to shrimp.WSV has been found to be highly pathogenic not only to penaeid shrimps, but also to a wide range of hosts which include marine crabs , copepods, freshwater crabs and prawns. Main objective of this study was detection and identification of white spot virus from wild shrimp and crabs population on the coastal waters of Hormozgan Province.The samples were collected from three area seasonally include: coastal waters of Qeshm Island, Hengam Island and Jask. In this survey have been examined 1080 shrimp from each species of P.indicus, P.semisulcatus, P.merguiensis, Metapenaeus affinis and 1080 crabs (gill organs) by PCR and histopathological methods. Diagnostic kit for this survey have been prepared from Genesis Biotechnology CO.in Malaysia, so called "Single-Tube Nested PCR for WSSV". The analysis results revealed that all samples which examined from these area were free from WSV. Following PCR tests that were negative for all samples so no observed any damages of histology due to WSV on gills