125 research outputs found

    Optimization of Cutting Conditions in End Milling Process with the Approach of Particle Swarm Optimization

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    Milling is one of the progressive enhancements of miniaturized technologies which has wide range of application in industries and other related areas. Milling like any metal cutting operation is used with an objective of optimizing surface roughness at micro level and economic performance at macro level. In addition to surface finish, modern manufacturers do not want any compromise on the achievement of high quality, dimensional accuracy, high production rate, minimum wear on the cutting tools, cost saving and increase of the performance of the product with minimum environmental hazards. In order to optimize the surface finish, the empirical relationships between input and output variables should be established in order to predict the output. Optimization of these predictive models helps us to select appropriate input variables for achieving the best output performance. In this paper, four input variables are selected and surface roughness is taken as output variable. Particle swarm optimization technique is used for finding the optimum set of values of input variables and the results are compared with those obtained by GA optimization in the literature

    Life History Traits of Talicada nyseus (Lepidoptera: Lycaenidae) Butterfly Under Laboratory Conditions

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    The butterfly Talicada nyseus G. (Lepidoptera: Lycaenidae) is abundant in India and Sri Lanka (Karunaratne, et al., 2002). In India, this butterfly is chiefly found in the peninsular area, Maharashtra, Karnataka, Punjab and foothills of the Himalayas (Singh, 2005). The host plants of this butterfly include Kalanchoe spp. (Saxifragales: Crassulaceae). Adult Talicada nyseus feed on nectar of surrounding flowering plants but are also reported to feed on lichens (Karunaratne, et al., 2002). Recently it has been discovered that Talicada nyseus is infected with maternally inherited Wolbachia bacteria (Ankola, et al., 2011; Salunke, et al., 2012) and exhibits a female biased sex ratio (Ankola, et al., 2011). It is suspected that the presence of the female biased sex ratio in this butterfly is caused by its endosybiont Wolbachia. As an endosymbiont, Wolbachia is known to cause female biased sex ratio in butterfly hosts by inducing two distinct reproductive anomalies: feminization of genetic males (Hiroki et al., 2004) and male killing (Jigginset al., 2001; Charlat et al., 2005). It is essential to record scientific data regarding the life history traits of Talicada nyseus naturally infected with Wolbachia. In the present report life history traits of Talicada nyseus which harbor Wolbachia infection were studied under controlled conditions. The individual Talicada nyseus specimens used for the study were collected from a laboratory reared population which was previously confirmed to be heavily infected with Wolbachia. Five individual mated pairs were used separately for the present study. The life cycle was analyzed at 28.09 ± 0.564° C. The data collected were statistically analyzed by paired t-test with the help of SPSS 7.5. Wolbachia infection in this butterfly was previously documented by Ankola etal. (2011). The fecundity of Talicada nyseus was found to be ranging from 61.6± 12.08 to 66.4 ± 17.75 (Table 1). The fecundity data obtained from the present study is in agreement with our previous report (Ankola et al., 2011). More than 95% hatchability was recorded during the present investigation indicating that there might not be male-killing induced by Wolbachia in Talicada nyseus (Jiggins et al., 2000; Charlat et al., 2007). The hatching time required for eggs ranged from 7.4 ± 1.83 to 9.6 ± 2.71 (Table 1). Furthermore, the time required for th

    Oscillations of the magnetic polarization in a Kondo impurity at finite magnetic fields

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    The electronic properties of a Kondo impurity are investigated in a magnetic field using linear response theory. The distribution of electrical charge and magnetic polarization are calculated in real space. The (small) magnetic field does not change the charge distribution. However, it unmasks the Kondo cloud. The (equal) weight of the d-electron components with their magnetic moment up and down is shifted and the compensating s-electron clouds don't cancel any longer (a requirement for an experimental detection of the Kondo cloud). In addition to the net magnetic polarization of the conduction electrons an oscillating magnetic polarization with a period of half the Fermi wave length is observed. However, this oscillating magnetic polarization does not show the long range behavior of Rudermann-Kittel-Kasuya-Yosida oscillations because the oscillations don't extend beyond the Kondo radius. They represent an internal electronic structure of the Kondo impurity in a magnetic field. PACS: 75.20.Hr, 71.23.An, 71.27.+

    Singular Fermi Liquids

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    An introductory survey of the theoretical ideas and calculations and the experimental results which depart from Landau Fermi-liquids is presented. Common themes and possible routes to the singularities leading to the breakdown of Landau Fermi liquids are categorized following an elementary discussion of the theory. Soluble examples of Singular Fermi liquids (often called Non-Fermi liquids) include models of impurities in metals with special symmetries and one-dimensional interacting fermions. A review of these is followed by a discussion of Singular Fermi liquids in a wide variety of experimental situations and theoretical models. These include the effects of low-energy collective fluctuations, gauge fields due either to symmetries in the hamiltonian or possible dynamically generated symmetries, fluctuations around quantum critical points, the normal state of high temperature superconductors and the two-dimensional metallic state. For the last three systems, the principal experimental results are summarized and the outstanding theoretical issues highlighted.Comment: 170 pages; submitted to Physics Reports; a single pdf file with high quality figures is available from http://www.lorentz.leidenuniv.nl/~saarloo

    Counseling and surveillance of obstetric risks for female childhood, adolescent, and young adult cancer survivors: recommendations from the International Late Effects of Childhood Cancer Guideline Harmonization Group

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    Female childhood, adolescent, and young adult cancer survivors have an increased risk of adverse pregnancy outcomes related to their cancer- or treatment-associated sequelae. Optimal care for childhood, adolescent, and young adult cancer survivors can be facilitated by clinical practice guidelines that identify specific adverse pregnancy outcomes and the clinical characteristics of at-risk subgroups. However, national guidelines are scarce and vary in content. Here, the International Late Effects of Childhood Cancer Guideline Harmonization Group offers recommendations for the counseling and surveillance of obstetrical risks of childhood, adolescent, and young adult survivors. A systematic literature search in MEDLINE database (through PubMed) to identify all available evidence published between January 1990 and December 2018. Published articles on pregnancy and perinatal or congenital risks in female cancer survivors were screened for eligibility. Study designs with a sample size larger than 40 pregnancies in childhood, adolescent, and young adult cancer survivors (diagnosed before the age of 25 years, not pregnant at that time) were eligible. This guideline from the International Late Effects of Childhood Cancer Guideline Harmonization Group systematically appraised the quality of available evidence for adverse obstetrical outcomes in childhood, adolescent, and young adult cancer survivors using Grading of Recommendations Assessment, Development, and Evaluation methodology and formulated recommendations to enhance evidence-based obstetrical care and preconception counseling of female childhood, adolescent, and young adult cancer survivors. Healthcare providers should discuss the risk of adverse obstetrical outcomes based on cancer treatment exposures with all female childhood, adolescent, and young adult cancer survivors of reproductive age, before conception. Healthcare providers should be aware that there is no evidence to support an increased risk of giving birth to a child with congenital anomalies (high-quality evidence). Survivors treated with radiotherapy to volumes exposing the uterus and their healthcare providers should be aware of the risk of adverse obstetrical outcomes such as miscarriage (moderate-quality evidence), premature birth (high-quality evidence), and low birthweight (high-quality evidence); therefore, high-risk obstetrical surveillance is recommended. Cardiomyopathy surveillance is reasonable before pregnancy or in the first trimester for all female survivors treated with anthracyclines and chest radiation. Female cancer survivors have increased risks of premature delivery and low birthweight associated with radiotherapy targeting the lower body and thereby exposing the uterus, which warrant high-risk pregnancy surveillance
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