3,045 research outputs found

    Treatment and Conditioning of Spent Ion Exchange Resin from Nuclear Power Plant

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    There are a number of liquid processes and waste streams at nuclear facilities (i.e. nuclear power plants, fuel reprocessing plants, nuclear research centers, etc.) that require treatment for process chemistry control reasons and/or the removal of radioactive contaminants. These processes may be for reactor primary coolants, the cleanup of spent fuel pools, liquid radioactive waste management systems, etc. One of the most common treatment methods for such aqueous streams is the use of ion exchange, which is a well developed technique that has been employed for many years in both the nuclear industry and in other industries. Nuclear power plant process water systems have typically used organic ion exchange resins to control system chemistry to minimize corrosion or the degradation of system components and to remove radioactive contaminants. Organic resins are also used in a number of chemical decontamination or cleaning processes for the regeneration of process water by reagents and for radionuclide removal. In this report we will describe the method to solidify this waste by cementization techniques methods. There are several techniques are available for treating and conditioning of ion exchange resins. One of such technique uses a matrix material, which can be used in the conditioning process. There is wide rang of potential materials available for the conditioning of low and intermediate level liquid wastes and at the end we will mechanically (compression strength) testify these cubes of different cement and resin composition, according to IAEA standards

    Assessment of Aging of Zr-2.5Nb Pressure Tubes for Use in Heavy Water Reactor

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    The pressure tubes of pressurized heavy water reactor (PHWR) operate under high temperature high pressure aqueous environment and are subjected to fast neutron irradiation. In order to assure the structural integrity of pressure tube during service, it is periodically examined by non-destructive examination (NDE) techniques. A typical Pressurized Heavy Water Reactor (PHWR) consists of few hundred horizontally placed coolant channels. The coolant channel comprises of a Zr-2.5% Nb pressure tube encircled by a Zircaloy-4 calandria tube and four garter spring spacers (Zr-2.5Nb-0.5Cu), which prevents these two tubes to come in contact during their service life. The pressure tube carries the nuclear fuel, high temperature high pressure heavy water coolant and is subjected to fast neutron irradiation. The integrity of pressure tube is central to the safety of PHWRs. To ensure this, they are periodically subjected to in-service inspection by nondestructive examination (NDE) techniques.  In this paper detailed study has been done on the operating conditions which lead to degradations in the pressure tube with respect to dimensional changes as a result of irradiation creep and growth, deterioration in mechanical properties due to irradiation embitterment, initiation and growth of new flaws like fretting damage due to debris and fuel element bearing pads. The absorbed hydrogen can also limit the life of a pressure tube due to the degradation mechanisms such as delayed hydride cracking (DHC), hydride blister formation and cracking and hydride embitterment. It is a also one of the regulatory requirement to periodically subject pressure tubes to in-service inspection by employing non-destructive examination techniques. All these aspects have been duly addressed in this paper. Keywords: pressure tube, zircalloy-4, irradiation damage, delayed hydride crackin

    Point - to - Point Virtual Private Network Based on IP Filtering and Rijndael Encryption Algorithm

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    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

    Medical images protection and authentication using hybrid DWT-DCT and SHA256-MD5 hash functions

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    © 2017 IEEE. This paper deals with a blind digital watermarking technique for the ownership protection and content authentication of X-ray and MRI medical images. Extreme care is required before embedding watermarking information in medical images, to protect the image quality to avoid the wrong diagnosis. The proposed watermarking technique contains a robust watermark for the ownership protection and fragile watermarks for the content authentication. In the watermarking technique, the medical image is divided into regions and the watermark information is embedded in both the transform domain and the spatial domain. The proposed watermarking technique was successfully tested on a variety of X-ray and MRI medical images and offered high peak signal to noise ratios, similarity structure index measure values and wavelet domain signal to noise rations

    Anlam açısından tasavvuf ve Gazzali’de tasavvuf düşüncesi

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    Bu makale tasavvufun anlamını çeşitli alimlerin görüşleri ışığında incelemeyi hedeflemekte; Gazzali’nin bir düşünce ve yol olarak tasavvuftan nasıl etkilendiğini ele almaktadır. Gazzaliye göre itidale yakın olan Tasavvuf; Allah’a Peygamber’e, ahiret gününe iman etme, nefsi heva, makam, mal gibi dünyevi tutkulardan arındırma, dünyevi meşguliyetlerden kaçma ve sadece Allah’a yönelmeyi ifade etmektedir. Gazzali bizlere Tasavvufun kalkanlarını ilham, zühd, Allah sevgisi olarak belirtmiş ve gerçek anlamda Allah sevgisinin esas olduğunu ifade etmiştir

    Generalization of Individual Differences in Second Language Learning

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    This commentary is based on the analyses of the participants’ responses provided in written form while filling the questionnaires. The purpose of the study was to identify and analyze factors in individuals’ experiences about second language acquisition.  The study was conducted through a research questionnaire. The questions were designed for particular outcomes needed for the research. The research was to find motivational, social, and demographic factors in learning second language. The research participants were the successful users of second language. The paper also discussed the different influences from society, and profession which are a support to learn second language or sometimes these influences work as hindrance. Questionnaire also dealt with the usefulness of language books and effectiveness of language teachers. The project involves 4 participants who filled in the answers. 50% of them have provided very short answers but the ideas are understandable and interpretable, the rest gave detailed responses which remained more supportive for the analyses. Over all it was to obtain a general view about the above mentioned influential factors which may result positive or negative during the process of second language acquisition.

    Policy Interventions for the Development of the Blue Economy in Bangladesh

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    Between 2012 and 2014, disputes over maritime boundary with Myanmar and India were favorably settled for Bangladesh, resulting in the expansion of its territorial waters of more than 30% and the country received entitlement to 118,813 km2 in the Bay of Bengal. This achievement offers a wide range of new economic opportunities for jobs & growth around marine and coastal sectors such as marine fisheries, marine aquaculture, tourism, exploitation of natural resources, trade and energy. This created new opportunities to exploited the untapped potential of these waters. The challenge will be to develop smart and sustainable solutions to meet the economics needs of Bangladesh in this area. This paper presents the policy interventions that will contribute to impulse the development of the Blue Economy in Bangladesh. This was accomplished through an analysis of the institutional, commercial and environmental context of a set of selected sectors and the identification of the major areas of policy intervention in a near future. The analysis reflects therefore the point of view of all key stakeholders including practitioners, entrepreneurs, researchers, academics and representatives of the civil society

    Structural efficiency of hollow reinforced concrete beams subjected to partial uniformly distributed loading

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    Reinforced concrete (RC) beams containing a longitudinal cavity have become an innovative development and advantage for economic purposes of light-weight members without largely affecting their resistance against the applied loads. This type of openings can also be used for maintenance purposes and usage space of communication lines, pipelines, etc. RC beams are primarily loaded in the plane of the members, which are two-dimensional in a plane stress state and the dominant structural behaviours include bending, shear, or combination of both. In the present study, six numerical models of RC beams with and without openings were simulated by using commercial finite element software ANSYS to evaluate the structural behaviours of those beam models under the partial uniformly distributed load. Different parameters were assessed, including opening dimensions and shear reinforcement ratios. The obtained numerical results were analysed and verified and were found very close to those obtained from the experimental investigations in the literature. The increase of shear reinforcement ratio could enhance the flexural and shear capacities of the RC beams, and the results also showed that some models sustained flexural failure while the others sustained failure of combined bending and shear

    Automatic detection of potential buried archaeological sites in Saruq Al-Hadid, United Arab Emirates

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    The use of remote sensing in archaeological research allows the prospection of sub-surfaces in arid regions non- intrusively before the on-site investigation and excavation. While the actual detection method of expected buried archaeological structures is based on visual interpretation, this work provides a supporting archaeological guidance using remote sensing. The aim is to detect potential archaeological remains underneath the sand. This paper focuses on Saruq Al-Hadid surroundings, which is an archaeologist site discovered in 2002, located about 50 km south-east of Dubai, as archaeologists believe that other archaeological sites are potentially buried in the surroundings. The input data is derived from a combination of wavelength L-band Synthetic Aperture Radar (ALOS PALSAR), which is able to penetrate the sand, and multispectral optical images (Landsat 7). This paper develops a new strategy to help in the detection of suspected buried structures. The data fusion of surface roughness and spectral indices enables tackling the well-known limitation of SAR images and offers a set of pixels having an archaeological signature different from the manmade structures. The potential buried sites are then classified by performing a pixel-level unsupervised classification algorithm such as K-means cluster analysis. To test the performance of the proposed method, the results are compared with those obtained by visual interpretation
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