Determining The Minimum Distance Between Centers of Two Parallel Tunnels to Apply The Law of Super Position in Order to Calculate Subsidence by Using The Software FLAC 3D

Due to the development of cities as well as rapid population growth, urban traffic is increasing nowadays. Hence, to improve traffic flow, underground structures such as metro, especially in metropolises, are inevitable. This paper is a research on the twin tunnels Of Isfahan's metro between Shariaty station and Azadi station from the North towards the South. In this study, simultaneous drilling of subway's twin tunnels is simulated by means of Finite Difference Method (FDM) and FLAC 3D software. Moreover, the lowest distance between two tunnels is determined in a way that the Law of Super Position could be utilized to manually calculate the amount of surface subsidence, resulted by drilling two tunnels, by employing the results of the analysis of single tunnels without using simultaneous examination and simulation. In this paper, this distance is called "effective distance". For this purpose, first, the optimum dimensions of the model is chosen and then, five models with optimum dimensions will be analyzed separately, each of which in three steps. The results of analyses shows that the proportions (L/D) greater than or equal 2.80, the Law of Super Position can be applied for prediction of surface subsidence, caused by twin tunnels' constructio

Evaluation of Toyserkan City's Water Contamination, due to The Existence of Radon, and Estimation of The Annual Effective Dose

The gas of 222Rn is one of the natural radioactivesources which is the decay product of 226Ra from 238U decay chain. Based on the latest information presented bythe United Nations Scientific committee in the field of the effects of atomic radiations, the respiration of Radon and its daughters (Plutonium, Bismuth and Lead), are one of the most important factors in human radiation inhalation, since Radon and its daughters account for approximately 1.2 msv of the total of 2.4 msv (mili Sievert) annual effective dose of natural radioactive sources produced. The fluctuation in the levels of Radon resolved in water, due to the hazards caused by the emitted radiations, is considerable; because studies show that long-term exposure to Radon increases the chances of lung cancer. The amount of radon in underground waters is more than that of surface waters. If water is exposed to free air, especially when it’s mixed as well, a considerable amount of its radon content is released. In this paper, Radon concentration (Bq/L) in waters of the wells and springs located in Toyserkan, is measured using Lucas chamber technique by means of a light weighted and transportable machine namely PRASSI (SFLENAmod5s). The results showed that the radon density in four measured samples in the waters of this region exceed 10 Bq/L, the allowable amount determined by the US Environmental Protection Agency (USEPA). For the cases where the concentration is high, is it proposed that drinkable water be preserved in open pools or at least waterfalls be used in order to agitate the water to release itsradon content. It is better to install a system for settling and exposing the water to air so that Radon and its decay products are dispersed and the contamination problem is solved

Sustainable Design and Water Resources Management

Among the direct environmental consequences of construction,the most significant is its consumption of water and other resources. Water is the origin of every form of life. It is a habitat,an aliment ,a means of production and transport,and a commodity.By its very nature, water creates networks: it is linked to other natural resources, land, forests, biodiversity, etc. Aquatic systems are interconnected; environmental problems have repercussions from one end to the other of a hydrographic basin. Various groups and stakeholders use water for their needs. Construction is believed to consume around half of all the resources humans take from nature. Sustainable building and construction, is a holistic, multidisciplinary approach.This approach is increasingly being advocated for buildingsandinfrastructure. Energy efficiency in buildings has become a key factor that has a great impact of energy security,optimization of energy of structure and energy efficiency improvement. Furthermore, this Article is aimed to initiate implementing sustainable design of building construction in reduction of consumption of energy resources specially water and present suggestions for conservation ofwater resources

Optimal density determination of bouguer anomaly using fractal analysis (Case of study: Charak area,IRAN)

In exploration geophysics the main and initial aim is to determine density of under-research goals which have certain density difference with the host rock. Therefore, we state a method in this paper to determine the density of bouguer plate, the so-called variogram method based on fractal geometry. This method is based on minimizing surface roughness of bouguer anomaly. The fractal dimension of surface has been used as surface roughness of bouguer anomaly. Using this method, the optimal density of Charak area insouth of Hormozgan province can be determined which is 2/7 g/cfor the under-research area. This determined density has been used to correct and investigate its results about the isostasy of the studied area and results well-coincided with the geology of the area and dug exploratory holes in the text area

Evaluation of Toyserkan City Water Contamination, due to the existence of Radon, and Estimation of the annual effective dose

The gas of 222 Rn is one of the natural radioactivesources which is the decay product of 226 Ra from 238U decay chain. Based on the latest information presented bythe United Nations Scientific committee in the field of the effects of atomic radiations, the respiration of Radon and its daughters (Plutonium, Bismuth and Lead), are one of the most important factors in human radiation inhalation, since Radon and its daughters account for approximately 1.2 msv of the total of 2.4 msv (mili Sievert) annual effective dose of natural radioactive sources produced. The fluctuation in the levels of Radon resolved in water, due to the hazards caused by the emitted radiations, is considerable; because studies show that longterm exposure to Radon increases the chances of lung cancer. The amount of radon in underground waters is more than that of surface waters. If water is exposed to free air, especially when it's mixed as well, a considerable amount of its radon content is released. In this paper, Radon concentration (Bq/L) in waters of the wells and springs located in Toyserkan, is measured using Lucas chamber technique by means of a light weighted and transportable machine namelyPRASSI (SFLENAmod5s). The results showed that the radon density in four measured samples in the waters of this region exceed 10 Bq/L, the allowable amount determined by the US Environmental Protection Agency (USEPA). For the cases where the concentration is high, is it proposed that drinkable water be preserved in open pools or at least waterfalls be used in order to agitate the water to release itsradon content. It is better to install a system for settling and exposing the water to air so that Radon and its decay products are dispersed and the contamination problem is solved

Optimal Density Determination of Bouguer Anomaly Using Fractal Analysis (Case of study: Charak area,IRAN)

In exploration geophysics the main and initial aim is to determine density of under-research goals which have certain density difference with the host rock. Therefore, we state a method in this paper to determine the density of bouguer plate, the so-called variogram method based on fractal geometry. This method is based on minimizing surface roughness of bouguer anomaly. The fractal dimension of surface has been used as surface roughness of bouguer anomaly. Using this method, the optimal density of Charak area insouth of Hormozgan province can be determined which is 2/7 g/cfor the under-research area. This determined density has been used to correct and investigate its results about the isostasy of the studied area and results well-coincided with the geology of the area and dug exploratory holes in the text are

Master of Science

thesisThis research studies the passive dynamics of an under-actuated trotting quadruped. The goal of this project is to perform three-dimensional (3D) dynamic simulations of a trotting quadruped robot to find proper leg configurations and stiffness range, in order to achieve stable trotting gait. First, a 3D simulation framework that includes all the six degrees of freedom of the body is introduced. Directionally compliant legs together with different leg configurations are employed to achieve passive stability. Compliant legs passively support the body during stance phase and during flight phase a motor is used to retract the legs. Leg configurations in the robot's sagittal and frontal plane are introduced. Numerical experiments are conducted to search the design space of the leg, focusing on increasing the passive stability of the robot. Increased stability is defined as decreased pitching, rolling, and yawing motion of the robot. The results indicate that optimized leg parameters can guarantee passive stable trotting with reduced roll, pitch, and yaw. Studies suggest that a quadruped robot with compliant legs is dynamically stable while trotting. Results indicate that the robot based on a biological model (i.e., caudal inclination of humeri and cranial inclination of femora) has the best performance. Stiff springs at hips and shoulders, soft spring at knees and elbows, and stiff springs at ankles and wrists are recommended. The results of this project provide a conceptual framework for understanding the movements of a trotting quadruped

Evolution of the theoretical power spectrum of solar-like oscillations along the ascending phase on the red giant branch.

CoRoT and Kepler observations of red giants reveal rich spectra of non-radial solar-like oscillations allowing to probe their internal structure. An important question comes from the observation of mixed modes : When during the star’s ascension on the RGB are mixed-modes more likely to be detectable ? We follow the evolution of a star on the RGB and investigate the effect of its ascension on theoretical power spectrum. Equilibrium models (computed with the code ATON) represent four different stages of a star on the RGB. The mass of the star (1.5M") is in the typical mass range of stars observed by CoRoT and Kepler. We used a non-radial non-adiabatic code to compute the theoretical solar-like oscillations of these models. An important output of these calculations is the theoretical lifetimes of the modes. Then we computed the oscillation amplitudes through a stochastic excitation model. These computations allow us to draw theoretical power spectrum and discuss the possibility to observe mixed-modes at different evolutionary stages on the RGB. We found that structure modifications in a star ascending the RGB have an important impact on theoretical power spectrum of solar-like oscillations. Efficiencies of trapping and lifetimes of mixed modes are indeed strongly affected by this evolution