Design Of A Min-Sum Arborescence With Outage Costs

We present an integer programming formulation of the min-sum arborescence with node outage costs problem. The solution to the problem consists of selecting links to connect a set of terminal nodes to a root node with minimal expected annual cost, where the annual cost is the sum of annual links costs and annual outage costs. The links in the network are prone to failure and each terminal node has an associated outage cost, which is the economic cost incurred by the network user whenever that node is disabled from the central node due to failure of a link. We suggest a Lagrangian-based heuristic to get a good solution to this problem. This solution procedure also gives lower bounds to the optimal solution and is used to assess the quality of the heuristic solution. Numerical experiments taken from instances with up to 100 nodes are used to evaluate the performance of the proposed heuristic

A Lagrangean Heuristic For The Degree Constrained Minimal Spanning Tree Problem

In this paper we present a new heuristic procedure to solve the degree constrained minimal spanning tree problem. This procedure uses Lagrangian relaxation of the integer programming formulation of the problem to get a lower bound for the optimal objective function value. A subgradient optimization method is used to find multipliers that give good lower bounds. A branch exchange procedure is used after each iteration of the subgradient optimization to generate a feasible solution from an infeasible Lagrangean solution. Computational results are given for problems with up to 300 nodes. The heuristic procedure presented here gives optimal solutions in most instances. For problem sets that were not solved optimally, the gap between the lower bound and the feasible solution was less than 10-2 percent

Lower Bounds for the Multiperiod Capacitated Minimal Spanning Tree with Node Outage Cost Design Problem

The Multiperiod Capacitated Minimal Spanning Tree With Node Outage Costs (MCMSTWOC) Design problem consists of scheduling the installation of links in a communication network so as to connect a set of terminal nodes S = [2,3...N] to a central node (node 1) with minimal present value of costs. The cost of the network is the sum of link layout cost and node outage costs. The link capacities limit the number of terminal nodes sharing a link. Node outage cost associated with each terminal node is the economic cost incurred by the network user whenever the terminal node is disabled due to failure of a link. In the network some of the terminal nodes are active at the beginning of the planning horizon while others are activated over time. The problem is formulated as an integer-programming problem. A Lagrangian relaxation method is used to find a lower bound for the optimal objective function value. Subgradient optimization method is used to find good lower bounds. This lower bound can be used to estimate the quality of the solution given by a heuristic

Dust in Mineral Processing

The generation of airborne dust is a significant problem for the mineral industry. Previous studies in the literat-ure concluded that surfactants were the most effective dust suppressant agents since they enhance the wetting characteristics of the material. However, personnel in the iron ore industry have reported that these agents were not effective. Why is it that surfactants are effective for materials like coal but not iron ore? If surfactants can not control dust levels, what other reagents should be considered

PROBIOTICS: THE UNDERVALUED CONQUERORS

ABSTRACTProbiotics or beneficial microorganisms†have recently acquired the status of blockbusters in the pharmaceutical industry. Despite being commerciallyavailable, little is known about the magnitude to which they can contribute to various disease conditions such as inflammatory bowel disease, allergy,immunity, etc. this review dwells into the various mechanisms of actions of probiotics and summarizes the numerous benefits of these daily usedproducts, including the recent advances. It also emphasizes on the possible unfavorable consequences, which can result due to their extensive use.Keywords: Probiotics, Allergy, Immunity, Inflammatory bowel disease

Insulin delivery: what is new in the queue?

Diabetes Mellitus (DM) is a cluster of  metabolic disorders with the shared feature of hyperglycemia which may be due to discrete etiopathogenesis. India stands to be the diabetic capital of the world, second only to China. After its discovery by Banting and Best, it has been established that insulin plays a fundamental role in the management of DM. In spite of insulin being in the market for so long, what still remains a challenge is the invasive approach of its administration. Conventional pharmacotherapeutic approaches of insulin delivery that have been available over the years are insulin syringes, pumps and pens. Upcoming innovative modes of insulin delivery include oral insulin, inhaled insulin, colonic insulin delivery, transdermal insulin, intra-peritoneal insulin, intra-nasal insulin, nano-technology etc. Constant research has been going on since many years to discover a route of administration for insulin that is minimally or noninvasive, effective, safe, convenient and cost-effective for patients. If successful, alternative routes of administration could revolutionize the treatment of DM and help improve patients’ quality of life

Process for the extracting oxygen and iron from iron oxide-containing ores

Oxygen and metallic iron are produced from an iron oxide-containing mineral, such as ilmenite, by extracting iron from the mineral with hydrochloric acid, separating solid residue from the resulting solution and drying same, electrolyzing the separated, iron chloride- containing solution to produce electrolytic iron and chlorine gas, combining the chlorine gas with water recovered from the drying and/or iron chloride-containing solution electrolysis steps of regenerate hydrochloric acid and recycling the hydrochloric acid to the extraction step. In an alternate embodiment, the chlorine gas is reacted with recovered water in the presence of a catalyst to produce hydrochloric acid which is recycled to the extraction step, thereby eliminating the need for water electrolysis and a separate hydrochloric acid regeneration step. In another alternate embodiment, electrolysis of the iron chloride-containing solution is operated to produce oxygen instead of chlorine gas at the anode and hydrochloric acid is generated concurrently with plating of iron at the cathode. This hydrochloric acid is recycled to the extraction step, thereby eliminating the need for water electrolysis and a separate hydrochloric acid regeneration step.https://digitalcommons.mtu.edu/patents/1089/thumbnail.jp

Production of iron using environmentally-benign renewable or recycled reducing agents

To produce metallic iron from iron ore, a composition comprising a mass of material formed from a mixture of iron ore particles and particles of a reductant that is either a biomass material in particulate form or a plastic resinous material in particulate form is used. The reductant can also be a mixture of biomass material and resin in any proportions. The mass of material comprises at least one body having a shape adapted for smelting such as pellets, briquettes, pieces or lumps. The pellets have sufficient cohesion to maintain the shape into which they have been formed. The invention also provides a new method for smelting iron from its ore which comprises subdividing the ore into particles of a selected size, mixing the subdivided ore particles with particles of a biomass material or particles of a plastic resinous material or with mixtures thereof, forming a mass of the mixture into at least one body with a shape that is suited for smelting in a furnace and placing the body in a furnace and exposing it to sufficient heat to bring the iron therein to smelting temperature within the furnace to thereby produce metallic iron directly from the ore.https://digitalcommons.mtu.edu/patents/1025/thumbnail.jp

Analytic vortex solutions in an unusual Mexican hat potential

We introduce an unusual Mexican hat potential, a piecewise parabolic one, and we show that its vortex solutions can be found analytically, in contrast to the case of the standard Psi^4 field theory.Comment: 4 pages and 1 figure (missing in this version

Method for producing powder from polycrystalline inorganic material

A method for producing powder from polycrystalline inorganic material by contacting polycrystalline inorganic material with the vapor of one or more reduced alkali metals in an environment substantially free of oxygen for a period of time sufficient to cause disintegration of the polycrystalline inorganic material into powder. The polycrystalline inorganic material may consist of one or more oxides, sulfides, or silicates, or combinations thereof. The poly crystalline inorganic material may also comprise a rock or mineral, such as basalt or pyrite.https://digitalcommons.mtu.edu/patents/1070/thumbnail.jp