An investigation into approximate solutions for deterministic and stochastic multi-dimensional sequencing

A description is given of an investigation in detail into the validity of the overlap integral method for describing planar optical waveguide junctions. A comparison between the results of this method and that of a rigorous mode-matching approach is taken

A decision model for natural oil buying policy under uncertainty

A manufacturer, in a fast moving consumer goods industry, buys Natural oils from a number of oil suppliers world-wide. The prices of these oils are the major raw material cost in producing the consumer goods, which are also sold world-wide. The volatility in the international prices of the Natural oils has signi¯cant impact on the planning and budgets decisions. Since the oils are bought and the ¯nished products are sold in markets throughout the world, the manufacturer is exposed to a variety of market uncertainties and the resulting risks. These uncertainties are the raw material prices, the demand and the therefore the selling prices for the finished goods- all of which influence the profitability of the manufacturing firm. The risks can be minimised by entering into futures contract of appropriate duration, that is, by following a schedule of "forward"' purchase of oil (with specific series of future delivery dates) with the oil suppliers. We formulate this problem as a two-stage Stochastic Program (SP) using the futures and the spot prices for the Natural oil. This SP model gives robust decisions that hedge against the uncertainties in the Natural oil prices and the demand for the finished products. The uncertainty in the oil prices and the demand are modelled through a scenario generator. We have constructed a decision support system (DSS) that integrates the SP model, the scenario generator and the solution algorithm. This DSS also provides the decision maker a profile of the risk and return exposures for different policies

Revisiting lagrange relaxation (LR) for processing large-scale mixed integer programming (MIP) problems

Lagrangean Relaxation has been successfully applied to process many well known instances of NP-hard Mixed Integer Programming problems. In this paper we present a Lagrangean Relaxation based generic solver for processing Mixed Integer Programming problems. We choose the constraints, which are relaxed using a constraint classification scheme. The tactical issue of updating the Lagrange multiplier is addressed through sub-gradient optimisation; alternative rules for updating their values are investigated. The Lagrangean relaxation provides a lower bound to the original problem and the upper bound is calculated using a heuristic technique. The bounds obtained by the Lagrangean Relaxation based generic solver were used to warm-start the Branch and Bound algorithm; the performance of the generic solver and the effect of the alternative control settings are reported for a wide class of benchmark models. Finally, we present an alternative technique to calculate the upper bound, using a genetic algorithm that benefits from the mathematical structure of the constraints. The performance of the genetic algorithm is also presented

Software tools for stochastic programming: A Stochastic Programming Integrated Environment (SPInE)

SP models combine the paradigm of dynamic linear programming with modelling of random parameters, providing optimal decisions which hedge against future uncertainties. Advances in hardware as well as software techniques and solution methods have made SP a viable optimisation tool. We identify a growing need for modelling systems which support the creation and investigation of SP problems. Our SPInE system integrates a number of components which include a flexible modelling tool (based on stochastic extensions of the algebraic modelling languages AMPL and MPL), stochastic solvers, as well as special purpose scenario generators and database tools. We introduce an asset/liability management model and illustrate how SPInE can be used to create and process this model as a multistage SP application

Molecular docking studies of curcumin derivatives with multiple protein targets for procarcinogen activating enzyme inhibition

Curcumin derivatives which are very potent antioxidant, free radical scavenger and known inhibitor of dioxygenases have been extensively studied to explore their potential utilization in chemoprevention. The main objective of the present work is to perform a docking analysis of curcumin derivatives: Tetrahydrocurcumin (THC), Bisdemethoxy curcumin (BDC). Docking studies of these were performed using GOLD and AutoDock into a few well validated targets of anticancer therapy (COX-2, PhenolsulphoTransferases, Matrix metalloproteinases (MMPs), P450 and TNF-alpha). A good correlation was observed in binding affinity of THC and BDC against the targets indicating these derivatives are potent procarcinogen activating enzyme inhibitors. © 2010 Girija CR, et al

Effect of Dihedral and Anhedral on Lateral-Directional Stability of Rectangular Swept back Wing

Abstract: This paper investigates the probable effect a dihedral and an anhedral have on the Lateral-directional stability of an aircraft. In this paper we discuss the basic design of a rectangular swept back wing, designed in the XFLR5 software. We will apply different angles for both the dihedral and anhedral and analyse it using the XFLR5 Software. Our main goal would be to understand the stability criterion, mainly lateral-directional, of the airplane, analysing the graphs that help us understand lateral-directional static stability, compiling all the results and concluding our findings. Furthermore, we will be well-versed in the domain of static stability of an airplane with a rectangular planform which has swept back wings. The design and analysis part of this paper will wholly be covered in the XFLR5 software and the theoretically knowledge of the concept to stability will covered separately in the coming sections

JML Template Generation

The Java Modeling Language (JML) is a behavioral interface specific language designed to specify Java modules (which are Java classes and interfaces). Specifications are used to describe the intended functionality without considering the way it is implemented. In JML, if a user wants to write specifications for a Java file, he or she must undertake several steps. To help automate the process of creating annotations for method specifications, a tool Jmlspec was created. Jmlspec generated a file that refines the source file and has empty placeholders in which one can write specifications. Although Jmlspec worked with older versions of Java, it does not work with the current version of Java (Java 8). This thesis describes the implementation of a new version of the Jmlspec tool that is compatible with newest versions of Java. This tool will be more maintainable than the older version of Jmlspec and easier to extend

HUTCH DIVERTICULUM: A RARE CONGENITAL URINARY BLADDER DIVERTICULUM IN AN ELDERLY MALE PATIENT.

54 year old male patient presented with burning micturition and increased frequency of urination for the last two months. He also gives history of intermittent episodes of high grade fever with chills and rigors

Feasibility and accuracy of fetal echocardiography at routine 11 to 13 weeks 6 days ultrasound performed on unselected obstetric population in a tertiary maternity centre with high patient turnover

Background: Congenital heart defects (CHD) remain the most prevalent congenital malformations, with an estimated prevalence of 6-8 per 1000 live births. Routinely, fetal echo is performed around 18-22 weeks among high risk cases. A dedicated early fetal echo (EFEC) performed by experts between 11-16 weeks is emerging as an excellent screening tool among high risk cases. However, feasibility of obtaining such cardiac views during routine Nuchal Translucency scan by trained obstetricians, is yet to be known as there is limited time available with high patient turn over. Present study aimed to know the feasibility and accuracy of EFEC in unselected obstetric population in a tertiary maternity centre with high patient turnover.Methods: This was an observational cohort study from March 2015 to April 2017 at a tertiary maternity referral hospital. Singleton pregnant women undergoing routine 11-13+6 weeks scanning (NT scan) were recruited in the study including both high and low risk pregnancies. Possibility of obtaining 4 basic cardiac views within this limited time was assessed.Results: A total of 180 early fetal ECHO’s were performed during the course of this study. The 4-chamber view (79.44%) of the heart was the easiest parameter to visualize. RVOT (28.88%) was the most difficult view to be obtained. Complete visualization of all the cardiac views was possible in only 34 women (18.88%). The visualization rates of the cardiac views improved as the gestational age increased. TVS was essential to obtain cardiac views in 5 cases out of 138 (3.6%) in 12-13+6 scans. Whereas, TVS was essential to visualize cardiac views in 34 cases out of 42 (80.95%) between 11 weeks to 11 weeks 6 days. A total of 7 cardiac anomalies were detected during this study. There were 3 major and 4 minor cardiac malformations. Out of the 3 major anomalies, 2 were AVSDs which were diagnosed by EFEC. Minor defects were undetected.Conclusions: It is feasible to get the basic cardiac views in the limited time available to perform NT scan among unselected obstetric population in a tertiary maternity centre with a high turnover. Gestational age of 12 weeks and above seems to increase the accuracy. TVS is a useful adjunct throughout 11-14 weeks scan