Modeling batch annealing process using data mining techniques for cold rolled steel sheets

The annealing process is one of the important operations in production of cold rolled steel sheets, which significantly influences the final product quality of cold rolling mills. In this process, cold rolled coils are heated slowly to a desired temperature and then cooled. Modelling of annealing process (prediction of heating and cooling time and trend prediction of coil core temperature) is a very sophisticated and expensive work. Modelling of annealing process can be done by using of thermal models. In this paper, Modelling of steel annealing process is proposed by using data mining techniques. The main advantages of modelling with data mining techniques are: high speed in data processing, acceptable accuracy in obtained results and simplicity in using of this method. In this paper, after comparison of results of some data mining techniques, feed forward back propagation neural network is applied for annealing process modelling. A good correlation between results of this method and results of thermal models has been obtained

Avalanche frontiers in dissipative abelian sandpile model as off-critical SLE(2)

Avalanche frontiers in Abelian Sandpile Model (ASM) are random simple curves whose continuum limit is known to be a Schramm-Loewner Evolution (SLE) with diffusivity parameter $\kappa = 2$. In this paper we consider the dissipative ASM and study the statistics of the avalanche and wave frontiers for various rates of dissipation. We examine the scaling behavior of a number of functions such as the correlation length, the exponent of distribution function of loop lengths and gyration radius defined for waves and avalanches. We find that they do scale with the rate of dissipation. Two significant length scales are observed. For length scales much smaller than the correlation length, these curves show properties close to the critical curves and the corresponding diffusivity parameter is nearly the same as the critical limit. We interpret this as the ultra violet (UV) limit where $\kappa = 2$ corresponding to $c=-2$. For length scales much larger than the correlation length we find that the avalanche frontiers tend to Self-Avoiding Walk, the corresponding driving function is proportional to the Brownian motion with the diffusion parameter $\kappa =8/3$ corresponding to a field theory with $c = 0$. This is the infra red (IR) limit. Correspondingly the central charge decreases from the IR to the UV point.Comment: 11 Pages, 6 Figure

Higher Order and boundary Scaling Fields in the Abelian Sandpile Model

The Abelian Sandpile Model (ASM) is a paradigm of self-organized criticality (SOC) which is related to $c=-2$ conformal field theory. The conformal fields corresponding to some height clusters have been suggested before. Here we derive the first corrections to such fields, in a field theoretical approach, when the lattice parameter is non-vanishing and consider them in the presence of a boundary.Comment: 7 pages, no figure

Parameters of lower extremities alignment view in Iranian adult population

Normal axial alignment restoration in lower extremities is crucial for surgeons performing reconstructive surgeries. Since reference normal values of axial alignment are affected by age, sex, and ethical issues, we tried to scrutinize these parameters in Iranian adults and compare them with normal values in literatures. Through a cross-sectional design, standing axial alignment views of lower extremities were surveyed from 100 volunteers (50 males and 50 females) aged between 15-32 years. The lower extremities alignment variables were evaluated during two separate measurements. Total average values were used for comparison among genders. Tibiofemoral mechanical angle depicted mean varus of 1.5 degrees in an Iranian population that was significantly higher in male participants. The Mean angle between anatomical and mechanical axes of the femur was 5.7 ± 1.2º. The Knee joint was shown to be medially inclined 3.6 ± 1.7º in men comparing 2 ± 2º of women with a significant difference. Joint line congruence angle was medially inclined in all of the study participants with a mean of 1 ± 1.6º. To compare with anthropometric studies of western populations, Iranian participants had more varus lower limb alignment. It seemed mainly because of larger medially inclined knee joint (knee-joint obliquity). This finding along with more compensatory ankle valgus is similar to results of other Asian studies. Such racial variation should be considered in designing appropriate systems in reconstructive surgery

Parameters of lower extremities alignment view in Iranian adult population

Normal axial alignment restoration in lower extremities is crucial for surgeons performing reconstructive surgeries. Since reference normal values of axial alignment are affected by age, sex, and ethical issues, we tried to scrutinize these parameters in Iranian adults and compare them with normal values in literatures. Through a cross-sectional design, standing axial alignment views of lower extremities were surveyed from 100 volunteers (50 males and 50 females) aged between 15-32 years. The lower extremities alignment variables were evaluated during two separate measurements. Total average values were used for comparison among genders. Tibiofemoral mechanical angle depicted mean varus of 1.5 degrees in an Iranian population that was significantly higher in male participants. The Mean angle between anatomical and mechanical axes of the femur was 5.7 ± 1.2º. The Knee joint was shown to be medially inclined 3.6 ± 1.7º in men comparing 2 ± 2º of women with a significant difference. Joint line congruence angle was medially inclined in all of the study participants with a mean of 1 ± 1.6º. To compare with anthropometric studies of western populations, Iranian participants had more varus lower limb alignment. It seemed mainly because of larger medially inclined knee joint (knee-joint obliquity). This finding along with more compensatory ankle valgus is similar to results of other Asian studies. Such racial variation should be considered in designing appropriate systems in reconstructive surgery. © 2015 Tehran University of Medical Sciences. All rights reserved

The effect of adjuvant vitamin C after varicocele surgery on sperm quality and quantity in infertile men: A double blind placebo controlled clinical trial

Varicocele is one of the most common causes of male infertility and spontaneous pregnancy rate after varicocelectomy is only about 30. The most important seminal antioxidant is vitamin C but recent studies about the effects of vitamin C on spermatogenesis are controversial; therefore, we decided to evaluate its role after varicocelectomy. In a double blind randomized controlled clinical trial, 115 men with infertility and clinical varicocele with abnormal semen analyses were recruited. After surgery, the intervention group received vitamin C (250 mg bid) and the control group received placebo for three months. Mean sperm count, motility, and morphology index of two semen analyses (before and after surgery) were compared between the two groups. Univariate general linear model and stepwise linear regression were used in analysis. The mean age (±SD) of participants was 27.6±5.3 years. Vitamin C group had statistically significant better normal motility (20.8 vs. 12.6, P=0.041) and morphology (23.2 vs. 10.5, P<0.001) than placebo group. Considering the values prior to surgery as covariate, vitamin C was not effective on sperm count (P=0.091); but it improved sperm motility (P=0.016) and morphology (P<0.001) even after excluding the confounding effect of age (P=0.044 and P=0.001, respectively). Vitamin C was also an independent factor in predicting motility and normal morphology after surgery. Ascorbic acid can play a role as adjuvant treatment after varicocelectomy in infertile men

Spanning Trees in Random Satisfiability Problems

Working with tree graphs is always easier than with loopy ones and spanning trees are the closest tree-like structures to a given graph. We find a correspondence between the solutions of random K-satisfiability problem and those of spanning trees in the associated factor graph. We introduce a modified survey propagation algorithm which returns null edges of the factor graph and helps us to find satisfiable spanning trees. This allows us to study organization of satisfiable spanning trees in the space spanned by spanning trees.Comment: 12 pages, 5 figures, published versio

Morphology of proximal tibia in iranian population and its correlation with available prostheses

Background: Total knee arthroplasty is a complex procedure aiming to relieve pain and improve function. It is critical to select prosthesis that best cover the bone surfaces. Ethnicity may affect fitness of the components mainly designed for Caucasian populations. This study aimed to evaluate morphometric features of proximal tibia in Iranian population. Methods: During 2013, 150 consecutive patients (96 males and 54 females) form orthopedics department of Rasoul-Akram hospital with knee CT scan were randomly enrolled. We entered cases with apparent normal extremity alignment and bone maturity. Cases with history of fracture or conditions affecting knee profile were excluded. Standard cuts were simulated on CT scan. Anteroposterior (AP), mediolateral (ML) and aspect ratio (ML/AP) were measured for general morphology. Medial and lateral AP distance of tibia and their distance to tibial center were measured for checking symmetry. Results: Mean age was 43.0± 10.4 years (rang 11-80). Males showed significantly larger values in ML dimension and aspect ratio than females under a given AP value (p<0.001). However, the aspect ratio was suggestive of similar configuration of proximal tibia profiles among genders. Totally, close correlations were observed among simulated cuts and size-matched tibial components of the prostheses. However, better coverage was provided by some brands via designing interchangeable components for a given dimension. Medial and lateral condyles of tibia were almost symmetrical. Conclusion: Our findings indicated that some alterations in the shape of the components are needed to provide optimal coverage in Iranian population. We propose symmetrical configuration in designing tibial components as well