In this study, the effect of the thermal conductivity of phase change material (PCM) on the performance of thermal energy storage has been analyzed numerically. A horizontal concentric shell-and-tube latent heat thermal energy storage system (LHTESS) has been performed during the solidification process. Two types of paraffin wax with different melting temperatures and thermal conductivity were used as a PCM on the shell side, case1=0.265W/m.K and case2=0.311 W/m.K. Water has been used as heat transfer fluid (HTF) flow through in tube side. Ansys fluent has been used to analyze the model by taking into account phase change by the enthalpy method used to deal with phase transition. The numerical simulation assumptions were three-dimensional, transient, and laminar flow was used. The result for the PCMs of performance, temperature distribution, and liquid fraction during the discharge process were compared to each other. Furthermore, the Nusselt number was analyzed. The result showed that the increase in thermal conductivity of PCM reduces the time of the solidification process by 20%. The performance of LHTESS for case 2 is 63.2%, whereas for case1 is 54.6%.
Background: Atherosclerosis is well known related to age and certain cardiovascular diseases. Aging is one reason of arteries function deterioration which can cause loss of compliance and plaque accumulation, this effect increases by the presence of certain diseases such as hypertension and diabetes disease. Aim: To investigate the reduction of blood supply to the brain in patients with diabetes and hypertension with age and the role of resistive index in the diagnosis of reduced blood flow. Method: Patients with both diseases diabetic and hypertension were classified according to their age to identify the progression of the disease and factors influencing the carotid artery blood flow. By using ultrasound and standard Doppler techniq
... Show MoreReservoir characterization is an important component of hydrocarbon exploration and production, which requires the integration of different disciplines for accurate subsurface modeling. This comprehensive research paper delves into the complex interplay of rock materials, rock formation techniques, and geological modeling techniques for improving reservoir quality. The research plays an important role dominated by petrophysical factors such as porosity, shale volume, water content, and permeability—as important indicators of reservoir properties, fluid behavior, and hydrocarbon potential. It examines various rock cataloging techniques, focusing on rock aggregation techniques and self-organizing maps (SOMs) to identify specific and
... Show MoreProviding stress of poetry on the syllable-, the foot-, and the phonological word- levels is one of the essential objectives of Metrical Phonology Theory. The subsumed number and types of syllables, feet, and meters are steady in poetry compared to other literary texts that is why its analysis demonstrates one of the most outstanding and debatable metrical issues. The roots of Metrical Phonology Theory are derived from prosody which studies poetic meters and versification. In Arabic, the starting point of metrical analysis is prosodic analysis which can be attributed to يديهارفلا in the second half of the eighth century (A.D.). This study aims at pinpointing the values of two metrical parameters in modern Arabic poetry. To
... Show MoreTechnological development intersects with terrorism to a large extent, beyond the use of the Internet and social media, in order to spread ideas, obtain support and financing, and recruit new elements, to the area of tactics and techniques of terrorist attacks, and everything related to the arsenal of terrorist weapons in the present and future, while technology offers many benefits. In various fields, and contribute to achieving multiple gains for humanity, they provide extremist and terrorist organizations and elements with a set of weapons and means through which they attempt to bypass monitoring and control efforts and the restrictions imposed on the use of weapons. They also help in planning and implementing their terrorist operations,
... Show MoreBackground: There is plenty of evidence
suggesting that involvement of several groups of
viruses in the development and / or acceleration of
Type 1 Diabetes Mellitus (T1DM).
Objective: To analyze the T- cell proliferation in
the presence of Coxsackie virus B5 (CVB5), Polio
and Adenovirus antigens in addition to assessment
of Interferon- gamma (IFN-γ), Interleukins (IL-10
and IL-6).
Methods: In 60 Iraqi T1DM children with recent
onset of T1DM, Lymphocyte proliferation was
analyzed using Methylthiazol tetrazolium (MTT)
assay by culturing Peripheral Blood Lymphocytes
(PBLs) with Coxsackie Virus B5 (CVB5),
Adenovirus, and Polio vaccine. Serum Interferon-γ,
IL-10 and IL-6 were quantified by sandw
: The need for means of transmitting data in a confidential and secure manner has become one of the most important subjects in the world of communications. Therefore, the search began for what would achieve not only the confidentiality of information sent through means of communication, but also high speed of transmission and minimal energy consumption, Thus, the encryption technology using DNA was developed which fulfills all these requirements [1]. The system proposes to achieve high protection of data sent over the Internet by applying the following objectives: 1. The message is encrypted using one of the DNA methods with a key generated by the Diffie-Hellman Ephemeral algorithm, part of this key is secret and this makes the pro
... Show MoreGhrelin and leptin are hunger hormones related to type 2 diabetes mellitus (T2DM), and the pathogenesis of T2DM is the abnormality in insulin secretion and insulin resistance (IR). The aim of this study is to evaluate ghrelin and leptin concentrations in blood and to specify the relationship of these hormones as dependent variables with some biochemical and clinical measurements in T2DM patients. In this study, forty one T2DM and forty three non-diabetes mellitus (non-DM) subjects, aged between 40-60 years and with normal weight, were enrolled. Fasting serum ghrelin and leptin were estimated by enzyme-linked immunosorbent assay (ELISA). In our results ghrelin was significantly increased, and leptin was significantly decreased, in T2DM pa
... Show MoreBackground: The world health organization estimates that worldwide 2 billion people still have iodine deficiency Objectives: Is to make comparison between the effect of identification of recurrent laryngeal nerve (RLN) and non-identification of the nerve on incidence of recurrent laryngeal nerve injury (RLNI) in different thyroidectomy procedures.
Type of the study: cross –sectional study.
Methods: 132 patients with goiters underwent thyroidectomy .Identification of RLN visually by exposure were done for agroup of them and non-identification of the nerves for the other group. The outcomes of RLNI in the two groupsanalyzed statistically for the effect of
... Show MoreImage steganography is undoubtedly significant in the field of secure multimedia communication. The undetectability and high payload capacity are two of the important characteristics of any form of steganography. In this paper, the level of image security is improved by combining the steganography and cryptography techniques in order to produce the secured image. The proposed method depends on using LSBs as an indicator for hiding encrypted bits in dual tree complex wavelet coefficient DT-CWT. The cover image is divided into non overlapping blocks of size (3*3). After that, a Key is produced by extracting the center pixel (pc) from each block to encrypt each character in the secret text. The cover image is converted using DT-CWT, then the p
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