Enabling RFID in retail

The past two years have witnessed an explosion of interest in radio-frequency identification and supporting technologies, due primarily to their rapidly expanding use in tracking grocery products through the supply chain. Currently such applications monitor store-keeping units (SKUs) rather than individual goods, as the relatively high cost of RFID deployment and the very low profit margin of supermarket products make item-level tagging impractical. Yet, economic and technical concerns aside, it is easy to envision a supermarket in which each item is tagged with an RFID label and all shopping carts feature RFID readers. The carts could potentially include onboard computers that recognize products placed inside and that display information and promotions retrieved wirelessly from the system back end. RFID-enabled smart phones, which are commercially available today and becoming increasingly popular, could carry out the same function. Item-level deployment of RFID technology would also allow for quick checkout aisles that scan all products at once and thus eliminate queues, which are consistently reported as one of the most negative aspects of supermarket shopping. A simple extension of this system would be to embed RFID devices in consumers' loyalty or frequent-shopper cards to identify individuals. This could expedite system login and charge the shopping cost directly to the customer's account at the point of sale-unless removed at the POS, item-level tags will inevitably follow the consumer home. This scenario undoubtedly raises numerous privacy concerns.     

Production scheduling with uncertain supply: a new solution to the open pit mining problem

The annual production scheduling of open pit mines determines an optimal sequence for annually extracting the mineralized material from the ground. The objective of the optimization process is usually to maximize the total Net Present Value (NPV) of the operation. Production scheduling is typically a Mixed Integer Programming (MIP) type problem containing uncertainty in the geologic input data and economic parameters involved. Major uncertainty affecting optimization is uncertainty in the mineralized materials (resource) available in the ground which constitutes an uncertain supply for mine production scheduling. A new optimization model is developed herein based on two-stage Stochastic Integer Programming (SIP) to integrate uncertain supply to optimization; past optimization methods assume certainty in the supply from the mineral resource. As input, the SIP model utilizes a set of multiple, stochastically simulated scenarios of the mineralized materials in the ground. This set of multiple, equally probable scenarios describes the uncertainty in the mineral resource available in the ground, and allows the proposed model to generate a single optimum production schedule. The method is applied for optimizing the annual production scheduling at a gold mine in Australia and benchmarked against a traditional scheduling method using the traditional single “average type” assessment of the mineral resource in the ground. In the case study presented herein, the schedule generated using the proposed SIP model resulted in approximately 10% higher NPV than the schedule derived from the traditional approach.     

Gamma irradiation of air-dried olive leaves: Effective decontamination and impact on the antioxidative properties and on phenolic compounds

Olive leaves are commercialized for their antioxidative value due to their valuable phenolic compounds. The present study aimed to evaluate the effect of gamma irradiation on microbial load, on antioxidative properties and on phenolic compounds of air-dried olive leaves. Irradiation was applied up to 25 kGy (5 kGy intervals) to powdered and intact samples. Total aerobic bacteria, yeast and mold, and lactic acid bacteria were counted after gamma irradiation. Decontamination was obtained at 20 kGy. The radioresistance of microbial population was high with D₁₀ values between 9.74 and 25.12 kGy. Besides, gamma irradiation up to 25 kGy was found to maintain the antioxidant capacity, molecular mass distribution of polyphenolics, total phenolics, ortho-diphenols, flavonoids, oleuropein, verbascoside and rutin contents.     

Looking ahead in pervasive computing: Challenges and opportunities in the era of cyber–physical convergence

The physical environment is becoming more and more saturated with computing and communication entities that interact among themselves, as well as with users: virtually everything will be enabled to source information and respond to appropriate stimuli. In this technology-rich scenario, real-world components interact with cyberspace via sensing, computing and communication elements, thus driving towards what is called the Cyber–Physical World (CPW) convergence. Information flows from the physical to the cyber world, and vice-versa, adapting the converged world to human behavior and social dynamics. Indeed humans are at the center of this converged world since information about the context in which they operate is the key element to adapt the CPW applications and services. Alongside, a new wave of (human) social networks and structures are emerging as important drivers for the development of novel communication and computing paradigms. In this article we present some of the research issues, challenges and opportunities in the convergence between the cyber and physical worlds. This article is not a comprehensive survey of all aspects of the CPW convergence. Instead, it presents some exciting research challenges and opportunities identified by members of the journal’s editorial board with a goal to stimulate new research activities in the emerging areas of CPW convergence.     

Stope design and geological uncertainty: Quantification of risk in conventional designs and a probabilistic alternative

This paper adopts risk-based concepts developed in open pit mining to the underground stoping environment and shows examples using data from Kidd Creek Mine, Ontario, Canada. Risk is quantified in terms of the uncertainty a conventional stope design has in expected: contained ore tones, grade and economic potential. In addition, a new probabilistic mathematical formulation optimizing the size, location and number of stopes in the presence of grade uncertainty is outlined and applied, to demonstrate the advantages of a user-defined level of acceptable risk. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 63–74, March–April, 2009.     

Glucoamylases production of Aspergillus niger in solid state fermentation using a continuous counter-current reactor

This work presents the continuous production of fungal biomass and glucoamylase by solid state fermentation (SSF) in a counter-current reactor adapted for this purpose. Pre-germinated conidia of Aspergillus niger were used as an inoculum, and sugarcane bagasse, embedded with a nutritive solution, was the solid support. The solids residence time distribution (RTD) was carried out by feeding one impule of blue-coloured humidified bagasse and its RTD was fixed at 20 h. This study demonstrated that the values of the measured parameters (pH, moisture, biomass, glucoamylases production) were similar to those reported for batch SSF using the same solid support and micro-organism. A marked increase in biomass occurred from the progressive compartment (from compartment 1 to 9) into the reactor and the enzyme production was important (40 IU g⁻¹ dry exit solids). No mycelium damage or sporulation was observed by microscopy analysis. The above results confirmed that the continuous production of enzymes by SSF under no sterile conditions was successful. Inoculation with pre-germinated conidia shortened the processing time and allowed control of the age of the mycelium in each compartment. Aeration was accomplished by natural convection and moisture content had to be controlled. This process can be applied to the continuous production of fungal biomass and metabolites in SSF with industrial applications using environmental-friendly biotechnology.     

On the Dynamics of Mining Operations in Open Pit Mines

In this paper, mining dynamics is defined as the relationship between the mining rate and movement of mining operations conducted on the benches of a surface mine. This relationship describes the intensity of the pit development in space, in order to meet ore demand at the mill over time. Meeting the mill ore demand is a key factor in optimizing production scheduling in surface mines. Displacement velocity of mining operations within cutbacks, or independent pit units, is introduced in the context of long-term mine planning. Displacement velocity allows the place and time of transition of the mining operations from one independent pit unit to another to be determined as the condition for meeting the mill ore demand. An application using data from Mt Keith Nickel Operations in Western Australia is used to elaborate on the methods presented.