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Investigation the Correlation between Thermal Bridging and Geometries in Concrete Buildings  [PDF]
Ali Vaseghi, Craig Capano
Journal of Building Construction and Planning Research (JBCPR) , 2023, DOI: 10.4236/jbcpr.2023.114006
Abstract:

This article focuses on the investigation of the correlation between thermal bridging and various geometric configurations. The article employs QuickField software for conducting three-dimensional steady-state heat transfer simulations to investigate the thermal behaviors of diverse geometric shapes. Significantly, this study involves the simulation of four distinct geometries including concrete circular, square, rectangular, and triangular column through an insulated concrete layer while all geometries maintain the consistent surface areas. The simulations yield findings indicating that circular thermal bridging has the best thermal performance, while rectangular thermal bridging displays comparatively the lowest thermal efficiency. Furthermore, the results indicate that alterations in the perimeter of thermal bridge interfaces, while maintaining a constant area, exert a more pronounced influence on the thermal performance of the geometries compared to proportional changes in area while preserving the perimeter. The study’s findings aid building designers and architects in creating more energy-efficient structural and architectural elements by incorporating thermally efficient geometries and forms.

Application of Double Zero Metamaterials as Radar Absorbing Materials for the Reduction of Radar Cross Section
Homayoon Oraizi;Ali Abdolali;Noushin Vaseghi
PIER , 2010, DOI: 10.2528/PIER10010603
Abstract: We introduce and investigate the applications of double zero (DZR) metamaterials (having the real parts of permittivity and permeability equal to zero) as radar absorbing materials (RAMs). We consider a perfectly electric conductor (PEC) plate covered by several layers of DZR metamaterial coatings under an oblique plane wave incidence of arbitrary polarization. Several analytical formulas are derived for the realization of zero reflection from such structures. The angle of reflection in the DZR metamaterials becomes complex, which leads to the dissociation of the constant amplitude and equiphase planes. Then several examples of the applications of DZR metamaterials (in nondispersive and dispersive conditions) as RAMs and zero reflection coatings are provided. The characteristics and parameters of the DZR metamaterial media are determined in each case. The method of least squares is used to optimize the DZR coatings for the minimization of reflected power, which uses the combination of genetic algorithm and conjugate gradient method (GA-CG) to benefit from their advantages and avert their short comings.
A Novel Duality Between Permeability and Permittivity in a Concentric Sphere
Noushin Vaseghi;Ali Abdolali;Homayoon Oraizi
PIER Letters , 2010, DOI: 10.2528/PIERL10022104
Abstract: Consider a TEM plane wave incident on a spherical multilayer structure, then the following theorem is valid. This theorem reveals a duality between permeability and permittivity of media in a spherical multilayer structure. Theorem: Consider a sphere with arbitrary radius and parameters s (ε,μ) surrounded by a homogenous medium with parameters (ε,μ). Then consider the case that each medium is filled by its dual medium according to the interchange ε μ. Then, the forward and backward radar cross sections of the structure are the same for the two dual cases. However, in half planes φ=((2k+1)π)/4;(k=0,1,2,3), the interchange ε μ has no similar effect on the value of the radar cross section.
Finite
Behrouz Vaseghi,Mohammad Ali Pourmina,Saleh Mobayen
- , 2018, DOI: 10.1177/0142331217731617
Abstract: This paper considers the finite-time chaos synchronization of Chua chaotic oscillators based on the secure communication scheme in wireless sensor networks. The modified Chua oscillators are added to the base station and sensor nodes to generate the chaotic signals. Two methods are proposed for the finite-time synchronization of the modified Chua systems with uncertain parameters. In the first method, by using the Lyapunov stability theory, control law is suggested to achieve finite-time chaos synchronization. In order to increase the robustness of the controller, in the second method, a sliding mode controller is applied to the wireless sensor network. Synchronization between the base station and each of the sensor nodes is realized by multiplying a selection matrix by the specified chaotic signal, which is broadcasted by the base station to the sensor nodes. The mathematical proofs confirm that the proposed control law is correct and finally, the simulation results are presented to show the efficiency of the proposed technique
Development of a Novel Contactless Mechanocardiograph Device
Kouhyar Tavakolian,Faranak M. Zadeh,Yindar Chuo,Ali Vaseghi,Bozena Kaminska
International Journal of Telemedicine and Applications , 2008, DOI: 10.1155/2008/436870
Abstract: A novel method of detecting mechanical movement of the heart, Mechanocardiography (MCG), with no connection to the subject's body is presented. This measurement is based on radar technology and it has been proven through this research work that the acquired signal is highly correlated to the phonocardiograph signal and acceleration-based ballistocardiograph signal (BCG) recorded directly from the sternum. The heart rate and respiration rate have been extracted from the acquired signal as two possible physiological monitoring applications of the radar-based MCG device.
Sustainable Urban Development with Emphasis on Worn Out Texture Regeneration (Case Study: Isfahan, Iran)  [PDF]
Seyed Hamidreza Rozati, Mahshad Kazemzadeh, Amirmehdi Vaseghi
Current Urban Studies (CUS) , 2015, DOI: 10.4236/cus.2015.33020
Abstract: In recent years, due to the natural population growth and immigration, demand for houses in many of the large cities has risen. In spite of the fact that there are lots of lands which are abandoned or occupied with inappropriate uses as worn out texture in down towns, large cities have the problem of physical disintegration and unplanned development towards farming lands and suburb gardens which will result in huge unsustainability in different dimensions including economic, social, physical and environmental. Using the potentials of worn out textures in down towns is one of the solutions, which has been noted in literature of infill city developments in recent years in order to achieve a sustainable development. In this research, potentials of worn out texture of the city of Isfahan as a sustainable approach for future development have been investigated and some solutions have been suggested in order to have an optimal guidance which is based on regeneration of worn out textures. Methodology of the research is descriptive and analytic and is identically practical. The data have been gathered through librarian references, observation and questioners. After it, the area of worn out texture in down town was calculated and then through using clustering model, the number of houses needed in the city of Isfahan in the year 2025 was estimated. The results of the research indicate that in inner city context of Isfahan, due to the existence of the worn out textures, providing house is approachable and worn out texture regeneration can be considered as a sustainable approach for future urban development.
Structural Style in the Zagros Fold-Thrust Belt: The Gavbast Anticline, Coastal Fars  [PDF]
Hadi Vaseghi, Zahra Maleki, Mehran Arian
Open Journal of Geology (OJG) , 2016, DOI: 10.4236/ojg.2016.62011
Abstract: The Gavbast anticline is located in the Coastal Fars area of the Zagros folded belt, with north-south trend. The study anticline is restricted to the Bavush and Paskhand anticlines from North, the Gezzeh and Dehnow anticlines from South, the Varavi anticline from West and Nakh anticline from East (Figure 1). Description of fold geometry is important because they allow comparisons within and between folds and pattern-recognition in addition to occurrence and distribution of fold systems. The main goal of this paper is to define folding style of the Gavbast anticline and define structural features affected on them in the study area. In this research, we used the Tectonics FP software, Global Mapper software and geological maps and reports of Iranian National Oil Company. In addition, we used common classification of fold for indicating of folding mechanism of the Tabnak anticlinal structure. In the Gavbast anticline, fold style elements in all parts of this anticline have been calculated and analyzed for indicating of folding style mechanism. The results of this method have been shown the folding geometry changes accurately. The Gavbast anticline is gentle in structural sections D-D' and G-G' to K-K'. The anticline is an open fold in the L-L'？section. Also fold type in the E-E' and F-F' sections of the Gavbast anticline is steeply inclined sub-horizontal. These sections are located between the Razak (western part) and Hendurabi fault (eastern part). It seems that E-E' and F-F' parts in the Gavbast anticline have been suffered most deformation affected by the Razak and Hendurabi faults. At the end of, it seems that, the Razak and Hendurabi faults have major effects on folding style. This structure is a very good sample for effect of strike slip faults on the folding geometry and for this reason; the Gavbast anticline is considered a special structural style in the Zagros fold-thrust Belt.
Investigation of the Economic Impacts of Climate Change on Iran Agriculture: A Ricardian Approach (Case study: Wheat)
E. Vaseghi,A. Esmaeili
Journal of Science and Technology of Agriculture and Natural Resources , 2008,
Abstract: This study used a Ricardian approach to measure the impact of climate change on Iranian wheat production and analyzed potential impacts of further climate changes. The study utilized time series data for the period 1984-2004 pooled over 17 provinces. Results showed that climate change has significant nonlinear impacts on net revenue per hectare of wheat in Iran. The results also showed that rise in temperature and reduction in rainfall by the year 2100 will cause the reduction in land value by 41 %, because of increased greenhouse gas emission.
Marketing of Dutch Roses in County of Isfahan
M Bakhshoodeh,E Vaseghi
Journal of Science and Technology of Agriculture and Natural Resources , 2009,
Abstract: In this study, marketing situation, problems and services of Dutch Roses was investigated in Isfahan province as a main rose producing region in Iran. In this context, marketing margin, share of marketing agents in marketing margin, marketing cost coefficients and marketing efficiency were calculated and marketing path and marketing services of roses flower including harvesting, transportation, packing, sorting and standardization in major path were investigated. The data used in this study were gathered through completing questionnaires from 38 producers, wholesalers (cut flowers distributors) and retailers (flower sellers) and by interviewing four consulting companies in Dutch Roses production and marketing. The results indicated that 56.5 percent of producers are only engaged with production activities and not exporting flowers to either foreign countries or the other provinces in the country. In the main path, average coefficient of technical efficiency (78.17%) was found to be higher than that of price efficiency (34.67%) and based on the marketing efficiency, 108 Rial value added can be achieved from each 100 Rial marketing services cost..
APPENDICITIS IN PEDIATRICS: DIAGNOSTIC VALUE OF LEOKOCYTE COUNT, CRP, NEUTROPHIL TO LYMPHOCYTE RATIO
M NAZEM,M VASEGHI AMIRI
Journal of Research in Medical Sciences , 2000,
Abstract: Introduction. Appendicitis is the most common cause of acute surgical abdomen. However, many atypical manifestations of this disease make much difficulties in differential diagnosis. Diagnostic methods such as sonography or isotope scan are expensive or completely depend on sonographist's experience. So because there is no preoperative definite diagnostic test for appendicitis patients, it seems necessary to evaluate different variables to achieve this goal. Laboratory tests are inexpensive and available. Methods. A Series of 116 consecutive under 14 years old patients presenting with right lower quadrant pain were studied. All of the patients underwent operation and diagnosis was confirmed by histology. WBC count> 10000/mm3, neutr/Lymph>3/5 and positive CRP were indices of study. Findings. The sensitivity of WBC count above 10000/mm3, neutrophill to lymphocyte count ratio (>3/5) and positive CRP were 96, 76 and 70 percent, respectively. The specificity of them were 46, 65 and 68 percent. The sensitivity of combination of variables 53 percent and the specificity was 82 percent. Conclusion. These findings suggest that each of studied variable are usefull for diagnosis of acute appendicitis but the combination is usefull for rule- out the disease.
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