1,224 research outputs found
Shear design of HSC beams with combination of links and horizontal web steel
The existing recommendations in Eurocode 2 and the British Code of Practice for the shear design of beams are derived from research conducted essentially on normal-strength concrete (NSC) with cube strengths up to 50 MPa, and it was found that the shear strengths of high-strength concrete (HSC) members made with limestone aggregate are below the characteristic resistances of identical NSC members. Previous experimental tests have also shown that significant differences exist in the angle of crack of shear failure of NSC and HSC. This paper presents data from five beam tests, which demonstrate that HSC with limestone aggregate has a reduced shear strength compared with NSC made with gravel and thus shows a gap in knowledge in the design approach to shear resistance of HSC beams. Previous investigations have suggested that horizontal web steels can contribute to the overall shear resistance of a reinforced concrete member in conjunction with the other constituents, concrete, tension and shear steel. The paper also presents data from tests on 11 beam tests and shows that the shear resistance of HSC beams is highly dependent on dowel action resulting from horizontal web bars positioned at the centre of the depth of the beam. Past attempts to quantify this dowel action are investigated and an improved design rule is proposed
Effect of Dental Amalgam Silver Filling on Salivary Amylase Enzyme
The largest source of mercury located in dental amalgam fillings people. In this study, mercury level in saliva of amalgam and non-amalgam human were compared as well as the level of α amylase has been detected. Materialsand methods: The concentration of mercury, silver, and activity of amylase in saliva were measured in 55 adult study subjects. The mercury contents were determined by cold–vapor atomic absorption spectrometry. Results: The concentration of mercury in the serum was significantly higher in subjects with dental amalgam fillings (n = 25) compared to the non-amalgam group (n = 30) (p<0.01). The activity of α-amylase has significantly decreased in amalgam group. Conclusion: Higher amount of amalgam fillings synchronized with a lower activity of a- amylase.     Keywords:-Mercury, silver , α-amylas
File compression using probabilistic grammars and LR parsing
Data compression, the reduction in size of the physical representation
of data being stored or transmitted, has long been of interest both as a research topic and as a practical technique. Different methods are used
for encoding different classes of data files. The purpose of this research
is to compress a class of highly redundant data files whose contents are
partially described by a context-free grammar (i.e. text files containing
computer programs).
An encoding technique is developed for the removal of structural
dependancy due to the context-free structure of such files. The technique
depends on a type of LR parsing method called LALR(K) (Lookahead LRM).
The encoder also pays particular attention to the encoding of editing
characters, comments, names and constants.
The encoded data maintains the exact information content of the
original data. Hence, a decoding technique (depending on the same
parsing method) is developed to recover the original information from
its compressed representation.
The technique is demonstrated by compressing Pascal programs. An
optimal coding scheme (based on Huffman codes) is used to encode the
parsing alternatives in each parsing state. The decoder uses these codes
during the decoding phase. Also Huffman codes, based on the probability
of the symbols c oncerned, are used when coding editing characterst
comments, names and constants. The sizes of the parsing tables (and
subsequently the encoding tables) were considerably reduced by splitting
them into a number of sub-tables.
The minimum and the average code length of the average program are
derived from two different matrices. These matrices are constructed
from a probabilistic grammar, and the language generated by this grammar.
Finally, various comparisons are made with a related encoding method by
using a simple context-free language
A Proposed Methodology for Identifying and Evaluating an E-Forms Application
In order to develop a specific methodology that can be followed by any organization or individual who needs tochoose the appropriate E-Forms application that could meet the required needs, this research proposes a methodology whichconsists of three phases: Identification phase, Evaluation phase and Testing phase. In the first phase, a general survey on EFormstypesandtechnologiesisintroducedwithfocusontherecenttrendsinorder
to identify which type mostly meets theuser's general requirements. In the second phase, an evaluation to make an accurate selection is made to some of the topcompeting applications supporting the type identified in first phase by using a specific evaluation methodology, in thisresearch three of the widely used evaluation methodologies are discussed, in addition to a simple evaluation methodologywhich has been proposed and implemented using "Microsoft Excel Sheets" application. Finally in the third phase, a real test ismade using the winner application resulting from the second phase, where a four-stage testing plan is proposed in order toachieve this purpose. As an example, the E-Forms technology which is based on "Extensible Markup Language (XML)" isidentified due to its features and capabilities. Then the evaluation is made to the top applications supporting this technology,where "Adobe's XML Forms Architecture (XFA)" technology is selected as a winner. This winner application then is tested,where samples of forms were designed to show the extraordinary features this technology can offer including digital signature.The test includes the use of a proposed offline forms' data gathering technique and uses "Oracle 10g" as the back-enddatabase. It also includes a website to publish the designed forms in addition to an application developed using "OracleDeveloper 10g" to process the forms' data for one of the designed samples in order to prove these forms' accuracy
Soft Soil Effect on Soft Storey Response
Multi-storied reinforced concrete frame (RCF) buildings with open first storey to provide parking space is common in Dhaka city, the capital of Bangladesh. Such buildings are likely to produce soft storey action when subjected to earthquake loadings. Bangladesh building code places Dhaka in a moderate earthquake zone with a zone coefficient (Z) value of 0.15. Several soft soil sites exist in the city, most of which have been created by filling up of low lands and water bodies without proper compaction. Such soft soil sites are likely to produce major site amplification effects during earthquakes. One-dimensional wave propagation using the computer program SHAKE is used for selected soft soil profile of Dhaka. In the absence of measured shear wave velocity data, empirical relations are used to obtain shear wave velocity from Standard Penetration Test (SPT) data. Ground motion time histories are obtained for different input motions. Due to the absence of strong motion records for Dhaka city, US and Japanese strong motion records for four different earthquakes were used as input (outcrop) motion. Two-dimensional finite element models of six and ten storied RCF buildings with and without infill walls in the ground floor are subjected to the ground motion obtained for the specific site. Infill wall action is approximated with equivalent strut action. Elastic transient time history analysis is conducted using the computer program ETABS. To account for the energy dissipation in the structural elements due to inelastic action during strong earthquakes, the seismic response obtained is divided by a factor equal to the reduction factor R specified in the building code. Results thus obtained are compared to demonstrate the significant effect of soft soil site on the seismic response of buildings with soft storey
Child abuse and fabricated or induced illness in the ENT setting: a systematic review
Background
Child maltreatment is persistently under-recognised. Given that a third of maltreated children may return with serious or fatal injuries, it is imperative that otolaryngologists who are in frequent contact with children are able to detect maltreatment at first presentation.
Objective of review
This review aims to identify ENT injuries, signs or symptoms that are indicative of physical abuse or fabricated or induced illness (child maltreatment).
Type of review
Systematic review.
Search strategy
An all-language search, developed in Medline Ovid and consisting of 76 key words, was conducted of published and grey literature across 10 databases from inception to July 2015, for primary observational studies involving children aged <18 years.
Evaluation method
Each relevant article underwent two independent reviews with full critical appraisal, applying strict quality standards.
Results
Of the 2448 studies identified and screened, 371 underwent full review, resulting in 38 included studies that detailed 122 maltreated children. Pharyngeal perforations (n = 20) were the most frequent abusive ENT injury, predominantly affecting neonates and infants, presenting with dysphagia, drooling, haemoptysis and surgical emphysema. At least 52% of children with abusive pharyngeal injuries had additional co-existent injuries. The majority of ear injuries were inflicted to the external ear (n = 11) and included auricular deformity, abrasions, petechiae, lacerations and burns. Fabricated or induced illness cases presented most commonly with recurrent, unexplained otorrhoea or ENT lesions that failed to heal despite appropriate therapy.
Conclusions
All clinicians should be familiar with the signs of child maltreatment. Pharyngeal injuries, or injuries to the external ear, presenting in young children without an explicit history of witnessed injury should prompt a child protection referral for full evaluation. Likewise, children who present with recurrent, or apparently intractable symptoms and signs despite appropriate treatment, should raise the possibility of fabricated or induced illness, and discussion with a child protection specialist is advised. Early recognition of possible child maltreatment and instigation of appropriate safeguarding measures are essential to prevent repetition and escalation of injury. This is of paramount importance to otolaryngologists, who have the potential to identify these children in their practice
Point - to - Point Virtual Private Network Based on IP Filtering and Rijndael Encryption Algorithm
The Rijndael algorithm was chosen to take advantage of its features and add recent technology to increase the confidentiality and security for the transfer of sensitive data on some important institutions. Rijndael algorithm (Advance Encryption Standard) is the Encryption of Symmetric Key, each one of the keys has size of 128 bit. Each round consists of several processing steps; one of them is depend on the encryption key. Therefore NEDRO program has been designed depending on Rijndael algorithm and updated by adding the key (Initialization Vector), in addition to taking into consideration the possibilities that could face the process of transmission of data between  two sides. Finally NEDRO program has implemented and tested practically between two points (User making encryption and Host making decryption or Host making encryption and User making decryption at the same time ) Keywords : Cryptography , Rijndael (AES) ,Data Security , Encryption , Decryptio
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