A simulation‐based algorithm for optimal pricing policy under demand uncertainty

We propose a simulation‐based algorithm for computing the optimal pricing policy for a product under uncertain demand dynamics. We consider a parameterized stochastic differential equation (SDE) model for the uncertain demand dynamics of the product over the planning horizon. In particular, we consider a dynamic model that is an extension of the Bass model. The performance of our algorithm is compared to that of a myopic pricing policy and is shown to give better results. Two significant advantages with our algorithm are as follows: (a) it does not require information on the system model parameters if the SDE system state is known via either a simulation device or real data, and (b) as it works efficiently even for high‐dimensional parameters, it uses the efficient smoothed functional gradient estimator.     

Profit margin,process improvement and capacity decisions in global manufacturing

We study two strategies that a company may employ for competing in global markets: high profit margin; and investment in process improvements. The strategy of high profit margin is associated with aggressive investment in new plants worldwide; and the strategy of process improvements is associated with increasing the effective capacity of existing plants, reducing manufacturing cost and increasing the plant's life cycle. Such plant decisions are complicated by country-specific parameters, e.g. tariff rate, tax rate, transportation cost and economic growth rate, which may vary widely from one country to another. We construct a simulation model that uses non-linear relationships among decision variables to explore insights, e.g.: (i) global conditions that would be synergistic with each of the two strategies; (ii) level of investment that would be justified in newly industrialized countries, in relation to the industrially mature countries; and (iii) shifts in investment in time and their relationship to the competitive strategies.     

Multifunctional glow discharge analyzer for spacecraft monitoring

In this study the main objective was to develop and demonstrate a glow discharge microplasma coupled to a miniature spectrometer for detection of fire signatures from pyrolyzing and burning spacecraft materials. Our experimental results demonstrate that combustion-produced carbonaceous aerosols can serve to identify the burning materials. Demonstrating versatility for chemistry analysis, the plasma detector could differentiate carbonaceous aerosols with different C/H ratios and distinguish inorganic samples such as salts and metal oxides from carbonaceous aerosols. In addition, in situ analysis of aerosol samples validated the microplasma’s analytical utility by linearity of its optical emission intensity with aerosol elemental composition.     

Mechanical and tribological properties of silicon carbide coating on Inconel alloy from liquid pre-ceramic precursor

Liquid polycarbosilane (LPCS) derived hard coatings of silicon carbide (SiC) were deposited on Inconel alloy at three different moderately high temperatures by chemical vapour deposition. The deposited films were characterized by X-ray diffractometry and Field emission scanning electron microscopy. Liquid PCS yielded a mixture of α-SiC and β-SiC during decomposition having uniform round-shaped particles of dimension around 200–300 nm without extensive cracking and few discrete shaped particles were also found to form at higher temperature (i.e. 1100 °C and 1200 °C) deposited films. The coated samples showed substantial increment in hardness and fracture toughness as compared to the uncoated sample. The fracture toughness (K_IC) values of the deposited films were in the range of 6.7–10.7 MPa(m)^1/2. The tribological properties and hardness of the films were also found to vary with deposition temperature. The scratch tracks of the films revealed that brittle failures occurred in all SiC coated substrates.     

Linearizer for pulse-shaping of received pulse in ultra-wideband radio systems

This paper presents a novel concept of pulse-shaping in an ultra-wide band radio system. Instead of attempting to design an antenna with flat group delay, the emphasis has been shifted to the signal processing aspect of pulse shaping. The received pulse which has broadened due to non-linear phase response of the propagating channel is shaped back closer to the ideal pulse using a linearizer. The block schematic of the linearizer is presented along with simulated results. Though only a Rayleigh first order pulse has been used for simulation purpose, the method can easily be generalized to incorporate other pulse shapes.     

0.40% Bipolar Strain in Lead Free BNT–KNN System Modified with Li,Ta and Sb

In this work we demonstrate a large electric field‐induced bipolar strain ~0.40% in Li, Ta and Sb modified BNT–KNN ((1?x) Bi_0.5Na_0.5TiO₃–xK_0.47Na_0.47Li_0.06 Nb_0.74Sb_0.06Ta_0.2O₃) system. The morphotropic phase boundary (MPB) of the system between rhombohedral and tetragonal phases lies in the range 0.02 ≤ x ≤ 0.06, beyond which all compositions (up to x < 0.15) were found to be tetragonal. A clear trade‐off between the large strain values and achievable d₃₃, k_p for a particular composition was noted. It is shown that while for x = 0.03, d₃₃ 169 pC/N, k_p 49% and strain ~0.13% were obtained, for x = 0.08 with 0.40% strain, d₃₃ and k_p values decreased drastically.     

Grain Size Distributions after Single Hit Deformation of a Segregated, Commercial Nb-Containing Steel: Prediction and Experiment

The present investigation examines the applicability of the Dutta–Sellars equations in predicting the recrystallized grain sizes following deformation for a 0.046 wt pct Nb-bearing, commercially produced steel with a segregated solute content (from continuous casting). The investigation considered initial unimodal and bimodal grain size distributions before deformation that were generated by reheating the steel to 1498 K and 1423 K (1225 °C and 1150 °C), respectively. It was found that the reheated grain size distribution (separated into grain size classes) could be related to the solute-rich (smaller grain size classes) and solute-depleted (larger grain size classes) regions. The use of these relationships and a simple halving of the grain size within the distribution on recrystallization (used previously for homogenized samples of this steel) were found to be appropriate in the grain size class-based use of the Dutta–Sellars equations with respect to mode and maximum grain sizes after hot deformation and holding. This approach successfully predicted (confirmed by experiment) the grain size distribution after deformation in the presence of Nb segregation from continuous casting.     

Application of electromagnetic impact technique for welding copper-to-stainless steel sheets

The ability to manufacture a product using different metal combinations greatly increases flexibility in design and production. Joining of dissimilar metal combinations like Copper-to-Stainless Steel (Cu-to-SS) is, however, a challenging task owing to the large differences in physical and chemical properties. The application of electromagnetic (EM) impact technique is demonstrated for welding copper (Cu) to stainless steel (SS) sheets. The welding Cu-to-SS is accomplished by using Al drivers to accelerate Cu and SS work sheets. The tensile shear strength test and the metallographic studies are carried out for Cu-to-SS EM welds.     

Spectral derivative feature coding for hyperspectral signature analysis

This paper presents a new approach to hyperspectral signature analysis, called spectral derivative feature coding (SDFC). It is derived from texture features used in texture classification to dictate gradient changes among adjacent bands in characterizing spectral variations so as to improve better spectral discrimination and classification. In order to evaluate its performance, two known binary coding methods, spectral analysis manager (SPAM) and spectral feature-based binary coding (SFBC) are used to conduct comparative analysis. Experimental results demonstrate that the proposed SDFC performs more effectively in capturing spectral characteristics than do SPAM and SFBC.     

Delta-opioid stimulation by BW373U86 promotes autonomic reactivity to stressors and alters attention-related cardiac responses in rabbits.

The nonpeptide δ-opioid agonist BW373U86 (3 to 300 μg/kg) was tested in rabbits for effects on heart rate, cardiac orienting and Pavlovian conditioned responses to tones, and unconditioned cardiac and somatomotor responses to signaled and unsignaled shocks. BW373U86 did not alter shock-evoked somatomotor reflexes and had few effects on the development or retention of Pavlovian conditioned heart rate discrimination. However, BW373U86 appeared to modulate cardiac conditioning indirectly, by facilitating sympathetic reflexes evoked by the signaled stressor, and the dose effect was ∪-shaped within the dose range tested. The pronounced tachycardiac effect of BW373U86 was completely blocked, or rapidly reversed, by the selective δ-opiate antagonist naltrindole. BW373U86 was more potent in increasing signaled than unsignaled shock-evoked tachycardia, suggesting release of an endogenous substance (e.g., a δ-opioid) because of the Pavlovian conditioning contingency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)