A hybrid algorithm for university course timetabling problem

A hybrid algorithm combining the genetic algorithm with the iterated local search algorithm is developed for solving university course timetabling problem. This hybrid algorithm combines the merits of genetic algorithm and iterated local search algorithm for its convergence to global optima at the same time avoiding being get trapped into local optima. This leads to intensification of the involved search space for solutions. It is applied on a number of benchmark university course timetabling problem instances of various complexities. Keywords: timetabling, optimization, metaheuristics, genetic algorithm, iterative local searc

How do people learn how to plan?

How does the brain learn how to plan? We reverse-engineer people's underlying learning mechanisms by combining rational process models of cognitive plasticity with recently developed empirical methods that allow us to trace the temporal evolution of people's planning strategies. We find that our Learned Value of Computation model (LVOC) accurately captures people's average learning curve. However, there were also substantial individual differences in metacognitive learning that are best understood in terms of multiple different learning mechanisms -- including strategy selection learning. Furthermore, we observed that LVOC could not fully capture people's ability to adaptively decide when to stop planning. We successfully extended the LVOC model to address these discrepancies. Our models broadly capture people's ability to improve their decision mechanisms and represent a significant step towards reverse-engineering how the brain learns increasingly more effective cognitive strategies through its interaction with the environment

Influence of Temperature on the Conformational Guided Physical Properties of Ultrathin Films of PLLA

Poly (L lactic acid) (PLLA) ultrathin films of various thicknesses were prepared by spin coating method and investigated by using vibrational spectroscopic techniques such as FTIR and Raman. The analysis has been done in two parts: first one is verification of structural mode to understand the visibility of characteristic band to confirm the PLLA structure; where interestingly, as the thickness of the film increased, the structural features were found to be more explicit. The second part of the study was to observe the features of the film having been annealed for 1 h in two separate temperatures, one at specific annealing temperature 120 °C and the other at 160 °C to enable PLLA chains to reorient to get crystallized from its soften state at two such specific temperatures. The isothermal crystallization behavior of PLLA film at 120 °C and 160 °C from the melt was monitored by FTIR as well as Raman spectroscopies. More importantly, the band at 921 cm-1 corresponds to α crystalline phase of PLLA has been observed even in this ultrathin film with the effective application of temperature as selected in this study.Defence Science Journal, Vol. 64, No. 3, May 2014, pp. 309-313, DOI:http://dx.doi.org/10.14429/dsj.64.732

A study to determine the knowledge and level of awareness of medical undergraduates about herbal medicines and herb-drug interactions

Background: The increasing usage of herbal medicines worldwide has increased the probability of co-administration of herbal and allopathic medicines. This may lead to serious safety concerns, including herb-drug interactions (HDIs). Many HDIs may be overlooked due to poor doctor-patient communication about herbal drug usage probably because of lack of knowledge of herbal medicines and HDIs among physicians. The study was thus planned to identify the knowledge and awareness of medical students regarding the use of herbal medicines and about HDIs, to help improve the teaching skills and curriculum development for medical students.Methods: 286 medical students of 2nd, 3rd and 4th year MBBS course completed the study. All the participants were asked to fill a self-administered questionnaire consisting of 15 questions which included both open-ended and close-ended questions related to age, sex, knowledge, awareness and usage of herbal medicines and about herb-drug interactions. Data was analyzed and expressed as counts and percentages.Results: Majority (95.45%) of the students were aware of the fact that herbs can be used as medicines. They were most familiar with the herbs tulsi, neem, turmeric, aloe, ashwagandha and ginger. 46.85% consider herbal medicines to be risk free, and majority (55.6%) were not aware of the fact that herbs can cause herb-drug interactions. Media and elderly family members were their most common sources of information regarding herbal medicines. Majority (75.17%) would prefer allopathic medicines over herbal medicines. Only 23.07% always informed the physician about their usage of herbal medicines, although most (84.96%) felt that history regarding use of herbal medicines should be taken. Majority were not aware of the regulatory status of herbal medicines.Conclusions: Lack of knowledge and awareness of medical students about herbal medicines and herb-drug interactions was seen in the study. There is a need to inform the students of allopathic system of medicine about the adverse outcomes of herbal medicines and the knowledge about herb-drug interactions should be a part of the medical curriculum

99mTc-DMSA (V) in Evaluation of Osteosarcoma: Comparative Studies with 18F-FDG PET/CT in Detection of Primary and Malignant Lesions

To evaluate the role of 99mTc-DMSA (V) and [18F]FDG PET-CT in management of patients with osteosarcoma, 22 patients were included in our study. All patients underwent both 99mTc-DMSA (V) and whole-body [18F]FDG PET-CT scans within an interval of 1 week. 555–740 MBq of 99mTc-DMSA (V) was injected i.v. the whole-body planar, SPECT images of primary site and chest were performed after 3-4 hours. [18F]FDG PET-CT images were obtained 60 minutes after i.v. injection of 370 MBq of F-18 FDG. Both FDG PET-CT (mean SUVmax = 7.1) and DMSA (V) scans showed abnormal uptake at primary site in all the 22 patients (100% sensitivity for both). Whole-body PET-CT detected metastasis in 11 pts (lung mets in 10 and lung + bone mets in 1 patient). Whole-body planar DMSA (V) and SPECT detected bone metastasis in one patient, lung mets in 7 patients and LN in 1 patient. HRCT of chest confirmed lung mets in 10 patients and inflammatory lesion in one patient. 7 patients positive for mets on DMSA (V) scan had higher uptake in lung lesions as compared to FDG uptake on PET-CT. Three patients who did not show any DMSA uptake had subcentimeter lung nodule. Resuts of both 99mTc-DMSA (V) (whole-body planar and SPECT imaging) and [18F]FDG PET-CT were comparable in evaluation of primary site lesions and metastatic lesions greater than 1 cm. Though 99mTc-DMSA (V) had higher uptake in the lesions as compared to [18F]FDG PET-CT, the only advantage [18F]FDG PET-CT had was that it could also detect subcentimeter lesions

Local convergence of a parameter based iteration with Holder continuous derivative in Banach spaces

[EN] The local convergence analysis of a parameter based iteration with Hölder continuous first derivative is studied for finding solutions of nonlinear equations in Banach spaces. It generalizes the local convergence analysis under Lipschitz continuous first derivative. The main contribution is to show the applicability to those problems for which Lipschitz condition fails without using higher order derivatives. An existence-uniqueness theorem along with the derivation of error bounds for the solution is established. Different numerical examples including nonlinear Hammerstein equation are solved. The radii of balls of convergence for them are obtained. Substantial improvements of these radii are found in comparison to some other existing methods under similar conditions for all examples considered.The authors thank the referees for their valuable comments which have improved the presentation of the paper. The authors thankfully acknowledge the financial assistance provided by Council of Scientific and Industrial Research (CSIR), New Delhi, India.Singh, S.; Gupta, DK.; Badoni, RP.; Martínez Molada, E.; Hueso Pagoaga, JL. (2017). Local convergence of a parameter based iteration with Holder continuous derivative in Banach spaces. CALCOLO. 54(2):527-539. doi:10.1007/s10092-016-0197-9S527539542Argyros, I.K., Hilout, S.: Numerical methods in nonlinear analysis. World Scientific Publ. Comp, New Jersey (2013)Argyros, I.K., Hilout, S., Tabatabai, M.A.: Mathematical modelling with applications in biosciences and engineering. Nova Publishers, New York (2011)Singh, S., Gupta, D.K., Martínez, E., Hueso, J.L.: Semilocal and local convergence of a fifth order iteration with Fréchet derivative satisfying Hölder condition. Appl. Math. Comput. 276, 266–277 (2016)Traub, J.F.: Iterative methods for the solution of equations. Prentice-Hall, Englewood Cliffs (1964)Rall, L.B.: Computational solution of nonlinear operator equations, reprint edn. R. E. Krieger, New York (2007)Cordero, A., Ezquerro, J.A., Hernández-Verón, M.A., Torregrosa, J.R.: On the local convergence of a fifth-order iterative method in Banach spaces. Appl. Math. Comput. 251, 396–403 (2015)Argyros, I.K., Hilout, A.S.: On the local convergence of fast two-step Newton-like methods for solving nonlinear equations. J. Comput. Appl. Math. 245, 1–9 (2013)Argyros, I.K., Behl, R., Motsa, S.S.: Local convergence of an efficient high convergence order method using hypothesis only on the first derivative. Algorithms 8, 1076–1087 (2015)Kantorovich, L.V., Akilov, G.P.: Functional analysis. Pergamon Press, Oxford (1982)Argyros, I.K., Magreñán, A.A.: A study on the local convergence and dynamics of Chebyshev-Halley-type methods free from second derivative. Numer. Algorithms 71, 1–23 (2016)Li, D., Liu, P., Kou, J.: An improvement ofthe Chebyshev-Halley methods free from second derivative. Appl. Math. Comput. 235, 221–225 (2014)Argyros, I.K., George, S.: Local convergence of deformed Halley method in Banach space under Holder continuity conditions. J. Nonlinear Sci. Appl. 8, 246–254 (2015)Argyros, I.K., Khattri, S.K.: Local convergence for a family of third order methods in Banach spaces. J. Math. 46, 53–62 (2014)Argyros, I.K., George, S., Magreñán, A.A.: Local convergence for multi-point-parametric Chebyshev-Halley-type methods of higher convergence order. J. Comput. Appl. Math. 282, 215–224 (2015)Argyros, I.K., George, S.: Local convergence of modified Halley-like methods with less computation of inversion. Novi. Sad. J. Math. 45, 47–58 (2015)Xiao, X.Y., Yin, H.W.: Increasing the order of convergence for iterative methods to solve nonlinear systems. Calcolo (2015). doi: 10.1007/s10092-015-0149-9Martínez, E., Singh, S., Hueso, J.L., Gupta, D.K.: Enlarging the convergence domain in local convergence studies for iterative methods in Banach spaces. Appl. Math. Comput. 281, 252–265 (2016

Gravity and Wind Load Path Analysis of a Light-Frame and a Traditional Timber Frame Building

The objective of this study was to compare structural load path and system behavior of a light-frame (LF) and a timber frame (TF) structure. This load path analysis is part of a broader research effort that compares LF to TF residential structures. Structural analysis software was used to create a model of each structure. The TF structure was composed of large-dimension timbers and structural insulated panels (SIPs). An equivalent LF structure was designed for comparison, following the guidelines of the International Residential Code. Results show that TF outperforms LF in resisting uplift, as well as in story drift. TF also provides load paths that are more resistant to the introduction of large openings and the loss of a central post. Observed axial loads in TF posts show smaller ranges compared with LF studs