A Sawtooth Permanent Magnetic Lattice for Ultracold Atoms and BECs

We propose a new permanent magnetic lattice for creating periodic arrays of Ioffe-Pritchard permanent magnetic microtraps for holding and controlling ultracold atoms and Bose-Einstein condensates (BECs). Lattice can be designed on thin layer of magnetic films such as $Tb_6$$Gd_10$$Fe_{80}$$Co_4$. In details, we investigate single layer and two crossed layers of sawtooth magnetic patterns with thicknesses of 50 and 500nm respectively with a periodicity of 1$\mu$m. Trap depth and frequencies can be changed via an applied bias field to handle tunneling rates between lattice sites. We present analytical expressions and using numerical calculations show that this lattice has non-zero potential minima to avoid majorana spin flips. One advantage of this lattice over previous ones is that it is easier to manufacture.Comment: 8 pages, 6 figure

Boosting performance of transactional memory through transactional read tracking and set associative locks

Multi-core processors have become so prevalent in server, desktop, and even embedded systems that they are considered the norm for modem computing systems. The trend is likely toward many-core processors with many more than just 2, 4, or 8 cores per CPU. To benefit from the increasing number of cores per chip, application developers have to develop parallel programs [1]. Traditional lock-based programming is too difficult and error prone for most of programmers and is the domain of experts. Deadlock, race, and other synchronization bugs are some of the challenges of lock-based programming. To make parallel programming mainstream, it is necessary to adapt parallel programming by the majority of programmers and not just experts, and thus simplifying parallel programming has become an important challenge. Transactional Memory (TM) is a promising programming model for managing concurrent accesses to the shared memory locations. Transactional memory allows a programmer to specify a section of a code to be "'transactional", and the underlying system guarantees atomic execution of the code. This simplifies parallel programming and reduces the possibility of synchronization bugs. This thesis develops several software- and hardware-based techniques to improve performance of existing transactional memory systems. The first technique is Transactional Read Tracking (TRT). TRT is a software-based approach that employs a locking mechanism for transactional read and write operations. The performance of TRT depends on memory access patterns of applications. In some cases, TRT falls behind the baseline scheme. To further improve performance of TRT, we introduce two hybrid methods that dynamically switches between TRT and the baseline scheme based on applications’ behavior. The second optimization technique is Set Associative Lock (SAL). Memory locations are mapped to a lock table in order to synchronize accesses to the shared memory locations. Direct mapped lock tables usually result in collision which leads to false aborts. In SAL, we increase associativity of the lock table to reduce false abort. While SAL improves performance in most of the applications, in some cases, it increases execution time due to overhead of lock tables in software. To cope with this problem, we propose Hardware-SAL (HW-SAL) which moves the set associative lock table to the hardware. As such, true power of set associativity will be harnessed without sacrificing performance

Improving Energy Efficiency in MANETs by Multi-Path Routing

Some multi-path routing algorithm in MANET, simultaneously send information to the destination through several directions to reduce end-to-end delay. In all these algorithms, the sent traffic through a path affects the adjacent path and unintentionally increases the delay due to the use of adjacent paths. Because, there are repetitive competitions among neighboring nodes, in order to obtain the joint channel in adjacent paths. The represented algorithm in this study tries to discover the distinct paths between source and destination nodes with using Omni directional antennas, to send information through these simultaneously. For this purpose, the number of active neighbors is counted in each direction with using a strategy. These criterions are effectively used to select routes. Proposed algorithm is based on AODV routing algorithm, and in the end it is compared with AOMDV, AODVM, and IZM-DSR algorithms which are multi-path routing algorithms based on AODV and DSR. Simulation results show that using the proposed algorithm creates a significant improvement in energy efficiency and reducing end-to-end delay

Seepage Through Different Concrete Cut Off Wall Connection Systems Case Study: Karkheh Storage Dam

Seepage and water flow is one of the most important factors in design of embankment dams. The seepage through the foundation of earth dams can be controlled using the concrete cut off walls. The hydraulic head reduces in connection zone of the cut off wall and core of the dam that results to high hydraulic gradients. As a result, erosion and water leakage may occur. In this regard, the design of concrete cut off wall connection to the clayey core of earth dam is important. In this research, the total flow and the hydraulic gradient are considered to study the seepage through different cut off wall connection systems. The Karkheh storage dam with a plastic concrete cut off wall is selected for the seepage analysis. Six different connection systems are modeled and the effect of physical and mechanical factors like, the cut off wall permeability and the geometry of the connection systems on the total flow and the maximum hydraulic gradient are investigated. The connection systems with minimum flow and hydraulic gradient are determined. According to the results, the cut off wall connection system is an important part that affects the flow in earth dams. In this regard, the connection system with the most effective characteristics and suitability in construction is determined

Stress-Strain Analysis of Different Concrete Cut Off Wall Connection Systems Case Study: Karkheh Storage Dam

The concrete cut off wall is usually used to control the seepage through the foundation of earth dams. It is usually made of plastic concrete. It can be connected to the core of the earth dam using different connection systems. The difference between cut off wall and core material results stress concentration in the connection zone. In fact the main cause is the large difference between stiffness of the cut off wall concrete and clayey core of the dam. This makes the stress-strain behavior complex in the connection zone. In the present study, six different details for the connection system of the cut off wall to the earth dam core were identified. The Karkheh storage dam in Iran with a plastic concrete cut off wall was selected as the case study for investigation of the behavior of different connection systems. The connection systems were modeled and the stress-strain behavior in connection zones was analyzed at the end of dam construction and steady state seepage through the dam. Eventually, the most appropriate connection with the best stress-strain distribution was determined. According to the results the stress strain behavior of different types of cut off connection systems are different. Indeed, the kind of connection between the cut off wall and the core influences the stress-strain distribution in the connection zone drastically. According to the results, the system No. 2 (thick concrete slab at the base level of the core) causes a better stress-strain distribution compared to the other methods of cut off wall connection with the core

An Analytical Model for Estimating the Vibration Frequency of Structures Located on the Pile Group in the Case of Floating Piles and End-bearing Pile

Exact estimation of vibration fundamental period of structures plays a vital role in their designing procedure. The proposition of a relatively exact expression which considers the effects of a pile group on the fundamental period of the structures was of less interest to previous researchers. This study aims to propose an analytical model and expression so as to estimate the free vibration period of the structures located on a pile group. To reach the objectives of this study, several numerical analyses has been carried out using the method of equivalent spring which takes into account the effects of soil-pile-structure interaction on the fundamental period of the structures. In the next step of the study the effects of a pile group on the fundamental period of the structures have been analyzed analytically. In this analytical study two cases have been considered for the piles which are end-bearing and floating piles. In the case of floating piles a five degrees-of-freedom analytical model and its corresponding expression have been proposed considering the soil-pile-structure system. The numerical modelling has been performed using the direct method due to the neglect of the soil in analytical expression and the results have been compared with those of the proposed analytical expression. The soil mass participation coefficient (λ) has been obtained using the discrepancy between the results of the two different methods to modify the analytical expression. In the case of end-bearing piles an analytical model with three degrees-of-freedom and its corresponding expressions has been proposed. Then the soil has been neglected and a new analytical expression has been proposed using the mass participation coefficients adopted from other researches to calculate the fundamental period of the structures. The comparison between the results of the proposed expression and those of case and numerical studies confirms that the proposed expressions benefit from a relative accuracy and can be used as an initial criterion in designing procedure

Influences of temporal evolution of ground motion frequency content on developed dynamic ratcheting in SDOF systems

Dynamic Ratcheting (DR) is a nonlinear dynamic phenomenon occurring in hysteretic damping systems. It means the structural plastic deformation increases asymmetrically in successive cycles under an earthquake excitation. Although it is generally recognized that DR is closely related to the frequency contents of an earthquake excitation applied to thestructure, no targeted analysis has been conducted on the influence of time- varying frequency content on occurrence and development of DR. This manuscript aims to analyze the influence of time evolution of DR-inducing ground motion frequency content on developed DR phenomenon in the Single Degree-Of-Freedom (SDOF) system with the Elastic-Perfectly-Plastic (EPP) hysteretic behavior. To survey the influence of time evolution of ground motion frequencycontent on the developed DR: In the first step, the three DR-inducing ground motion records were selected as excitations input of EPP SDOF systems. In the second step, time-varying frequency of ground motions were changed by shifting theirfrequency content  forward or backward in time using wavelet transform to produce altered versions records. In the final step, the displacement responses of EPP SDOF systems under selected records and their altered versions were compared. By analyzing the displacement response of EPP SDOF systems excited by selected ground motions and their altered versions, it can be found that the time-varying frequency content considerably influences the developed DR behavior in SDOF systems. In the selection of records for dynamic analysis of structures, time-varying frequency content could be further considered as an important characteristic variable for ground motion records

(2Z)-N-(4-Meth­oxy­phen­yl)-2-(4-meth­oxy­phenyl­imino)-2H-1,4-benzoxazin-3-amine

In the crystal structure of the title compound, C22H19N3O3, inter­molecular C—H⋯O hydrogen bonds link the mol­ecules into a zigzag chain parallel to the face diagonal of the ac plane. The meth­oxy phenyl rings make a dihdral angle of 32.38 (7)° and form dihedral angles of 0.66 (8) and 24.17 (7)° with the fused benzooxazine ring system

Predictors of Testis Cancer Mortality in Iran

Introduction: Testis cancer is a rare cancer that afflicts young men. although the incidence of testis cancer is increasing, the mortality rate is decreasing. This study examines the mortality of testicular cancer and its relationship with the human development index and its components in Iran during 2005-2015. Materials and Methods: Data of patients with testis cancer were collected from the Office of National Cancer Registry in the Ministry of Health and Medical Education (MOH&ME) during 2005-2015. An additional telephone survey was conducted by trained interviewers to collect data, including survival status, demographic characteristics, age of cancer diagnosis and other clinical profiles. Kaplan-Meier survival rates were calculated according to demographic characteristics, economic status, and residential area and socioeconomic status (SES). All the analyses were done using STATA software, version 14 (StataCorp. 2015). Results: From 2005 to 2015, 5886 testicular cancer cases were diagnosed among men in all age groups. Most patients (73.9%) were 15–49 years of age at the time of diagnosis, 26.1% were 50 years of age or older. Seminoma was diagnosed among 46.78% of the patients and non-seminoma among 42.28%. Factors which had impact on survival rate were age (P=0.001), tumor histology (P=0.02, hazard ratio=1.23[0.98-1.38]) and TNM stage (P=0.001, hazard ratio=1.2[0.92-1.28]). Patients who got married at the time of diagnosis more likely presented at earlier stages and had better overall testis cancer-specific survival than patients who were single, separated, widowed, or divorced (P=0.002, hazard ratio 1.27[1.09-1.49]). Testis cancer mortality rate was significantly higher in patients who did not graduate from high school and significantly higher in patients who were tenants (P=0.057, hazard ratio =1.132[0.996-1.28]). Conclusion: Testis cancer mortality is decreasing in Iran. Age, TNM stage and histology, and marital and economic status were factors influencing mortality rate