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This paper presents the implementation of simulated annealing (SA) method, an artificial intelligence technique, to solve the optimization problem known as the school bus routing problem (SBRP). A specific challenge in all artificial intelligence optimization techniques is the selection of appropriate value parameters. One contribution of this paper is the implementation of a design of experiments technique to provide statistical support for parameter selection. The SBRP is formulated as a 0–1 integer linear programming model, where the objective function is to minimize the total cost. Because this problem is combinatorial in nature, it is not possible to find exact solutions in an adequate time, calling for the use of an artificial intelligence optimization technique. The proposed technique is SA due to its modeling flexibility and processing speed. To demonstrate the performance of the proposed algorithm, several experiments with real instances were carried out, showing that the metaheuristic algorithm performs better in quality and time than the classic routing method.

Recently, a new approach to solve the outbound container location problem motivated by the Shanghai maritime terminals was published. This approach addresses the problem by decomposing it into two stages. The first stage is a mathematical programming model and the second stage is a heuristic algorithm whose objective is to minimize the total reshuffle movements executed during the loading operation. That study reports that the diagonal stacking configuration provides the best performance. Conversely, this paper documents the results of a study to observe the performance of the various staking strategies under different conditions that can occur regularly in real ports. The parameters that are varied are the number of tiers in each stack, the number of container weight levels, and the permitted bay utilization. The results show that although the diagonal stacking strategy does provide the best performance under some conditions, it does not yield the best performance in other parameter combinations. The horizontal strategy is found to perform best for most of the parameter combinations considered in this study.

The space allocation problem for outbound containers involves assigning containers to specific locations in the yard as they are delivered to the port. The problem is challenging because the arrival sequence is not known in advance, which makes it difficult to minimize container rehandling during the ship loading operation. This paper provides a heuristic procedure for the container space allocation problem employing reach stacker vehicles as container handling equipment. Procedures reported in the existing literature apply to rubber-tired gantry (RTG) cranes. Therefore, we are extending current research to the cases of port terminals that employ reach stacker vehicles, commonly used by small or medium size ports in emerging countries such as in Latin America. In addition, we adapted a procedure recently published in the literature. Empirical results show that the proposed heuristic yields better performance than the adapted heuristic. Another contribution of this paper is the formulation of a perfect information mathematical model which computes a lower bound on the number of rehandles required to load a group of containers given their arrival sequence to the port. The gap between the number of rehandle movements achieved by the proposed heuristic and the perfect information model is reported.

Port terminals consist of two interfaces for transferring cargo among transport modes: (1) the seaside or quayside interface and (2) the landside interface. At the seaside interface, cargo is loaded and unloaded from the vessels and stored temporarily at the yard. Landside operations consist of receiving and dispatching cargo from external trucks and rail. The increasing volumes of international trade are demanding more efficient cargo handling throughout the port logistic chain and coordination with the hinterland, hence attracting more attention from both practitioners and researchers on the landside interface of ports. Due to the high variability of truck arrivals with a significant concentration at peak hours, congestion at the access gates of ports and an unbalanced utilization of the resources occur. Truck appointment systems (TAS) have already been implemented in some ports as a coordination mechanism to reduce congestion at ports, balance demand and capacity, and reduce truck turnaround times. Based on the current situation faced by the Port of Arica, Chile, this paper aims to analyze potential configurations of a TAS and evaluate its impacts on yard operations, specifically in the reduction of container rehandles, as well as truck turnaround times. For this, a discrete-event simulation model and a heuristic procedure are proposed and experimentation is performed using historical data from the port terminal. Results indicate that implementing a TAS may significantly benefit yard operations in terms of reducing container rehandles as well as truck waiting times.

Radio frequency identification (RFID) is a technology most commonly used for the tracking and identification of objects. Optimally implementing RFID is challenging, especially in supply chain management where the use of passive tags is more common. Challenges in RFID implementation include, costs, standardization, privacy, performance, reliability and a need for greater collaboration. Systems integration will be expensive too in most current systems. Due to the nature of RF communications, many RFID systems involve multiple readers. Therefore, determining the number and position of reader antennas has a significant effect on success of the deployment. In this paper, we propose two optimization models and a GRASP metaheuristic that consider the effect of the orientation of antennas, the type of material to identify, and the interference from obstacles in a three-dimensional warehouse. The solution gives the minimal number of readers along with their positions for 100 % coverage of the tagged items.

An inventory problem of a company that specializes in cutting steel coils into rolls and sheets of steel is addressed in this paper. Rolls and sheets of steel require a high level of customization depending on the specifications by the end user. This causes complexity in the management of finished goods, mainly due to the wide variety of dimensions of the rolls and sheets that are in the storage area. Due to the great variety of products built for stock, it is not possible to define a specific location in the storage area to place a product. For a company located in Mexico, recent data show that the percentage of obsolete inventory (items stored more than 90 days) is 7 %. The objective of this work is to reduce this percentage to 0 %. From a time study, it was learned that searching for finished inventory averaged 15.5 min. This activity consumes a large amount of the available forklift operator time. This means that in situations during which the forklift operator is pressed for time, it may be necessary to abandon the search for the correct finished products in the storage, and instead ship products of more recent production. Over time, the repetition of this event generates increased rates of obsolete inventory. The proposal to solve the problem was to reduce the search times through the implementation of a system that identifies inventory using RFID technology. This will improve the quality of the stored information, and therefore reduce the rate of obsolescence.

Radio frequency identification (RFID) is a technology with numerous benefits in applications where objects have to be identified automatically. However, cost, fragile tags, collision and reading errors are some of issues to be concerned with in an RFID implementation. Mainly, this paper proposes a method for tag identification and a method for the selection of the binary codes to program on the tags in order to facilitate the identification process. For the identification method a heuristic based on Hamming distance is developed where the basic idea is to utilize the information obtained in consecutive read attempts to help identify a tag. For the selection method three models based on Hamming distance are also developed which strive to find the set with the greatest dissimilarity among the codes. Computer simulations are performed to verify the validity of the proposed methods.

Extractive metallurgy has used free or combined sulfur as both the raw material and the energy material in carrying out economical manufacture of several metals in millions of tons per year quantities over the past century. This has controlled carbon emissions in an unintentional fashion and out of necessity as the ores in many cases have been sulfides to start with. And the benefits of heat generation by the sulfides reacting with oxygen in the process steps have avoided the use of carbon as a fuel in providing the reaction temperatures. In this article, we will show the inherent benefits of “thiometallurgy,” which uses sulfur in the extraction of metals in alleviating CO2 and water vapor–greenhouse gas (GHG) emissions, as well as its ability to provide a cost-effective energy material solution. Such solutions are not only applicable to existing base metal production but, as the authors will show, also are applicable to newer processes in the production of other metals and chemicals, such as alkaline earth metals, titanium, and to an extent aluminum in an indirect fashion. Iron ores can also be treated with thiometallurgy to meet the ULCOS criterion of ultra-low carbon dioxide steel being studied in Europe. The concept of generating “thiopower” as an alternative energy approach is also introduced by the authors.

We examine how distance to a Veterans Health Administration (VHA) facility, patient hometown classification (e.g., small rural town), and service-connected disability are associated with veterans' utilization of radiation therapy services across the VHA and Medicare. In 2008, 45,914 dually-enrolled veteran patients received radiation therapy. Over 3-quarters (35,513) of the patients received radiation therapy from the Medicare program. Younger age, male gender, shorter distance to a VHA facility, and VHA priority or disability status increased the odds of utilizing the VHA. However, veterans residing in urban areas were less likely to utilize the VHA. Urban dwelling patients' utilization of Medicare instead of the VHA suggests a complex decision that incorporates geographic access to VHA services, financial implications of veteran priority status, and the potential availability of multiple sources of radiation therapy in competitive urban markets.

Personal health records (PHRs) are designed to help people manage information about their health. Over the past decade, there has been a proliferation of PHRs, but research regarding their effects on clinical, behavioral, and financial outcomes remains limited. The potential for PHRs to facilitate patient-centered care and health system transformation underscores the importance of embracing a broader perspective on PHR research.Drawing from the experiences of VA staff to evaluate the My HealtheVet (MHV) PHR, this article advocates for a health services research perspective on the study of PHR systems.We describe an organizing framework and research agenda, and offer insights that have emerged from our ongoing efforts regarding the design of PHR-related studies, the need to address PHR data ownership and consent, and the promotion of effective PHR research collaborations.These lessons are applicable to other PHR systems and the conduct of PHR research across different organizational contexts.

Common fuels—whether they are simple hydrocarbons or oxygenated hydrocarbons or carbohydrates—can be economically produced from the respective oxides of carbon and hydrogen by simple chemical reductions. These reactions are efficiently carried out by applying fundamentals of the reduction process.

The objective of this longitudinal study was to detect the relationship between the sense of coherence (SOC), which is an adaptive coping response, and depression in informal caregivers of stroke survivors across 2 years. One-hundred-fifteen veterans, who were hospitalized after experiencing an acute stroke, and their informal caregivers were enrolled prior to discharge. Data were collected via face-to-face in-home interviews at 1, 6, 12, 18, and 24 months after discharge. A linear mixed model was fitted to estimate the effects of the time-dependent covariates (SOC) while considering the dependence of outcome measures at repeated times. Based on the linear mixed model, caregivers with a stronger SOC were associated with lower levels of caregiver depression across 2 years following a stroke (p < 0.0001). SOC seems to be an important aspect of a caregiver's capacity to cope after tending to the needs of a stroke patient.

The reduced availability of providers and travel difficulties in rural areas may thwart older rural adults from getting the care they need for memory-related problems. The purpose of this study was to determine whether rural-urban differences exist in the probability of any service use of primary care physicians and mental health specialists in a full sample of older adults and in a subset of impaired respondents. In the full sample, rural respondents were 0.66 times as likely (p = .06) to have used primary care physicians for memory-related problems compared with urban respondents. In the subgroup, rural individuals were 0.26 times as likely (p = .02). In both groups, there were no rural-urban differences in the probability of mental health specialty use for memory-related problems. Further investigations are necessary to determine the causes.

An innovative concept for one of the lowest-cost carbon dioxide capture methods from power plants and other carbon-dioxide-emitting facilities is provided here. The concept is to use a novel electro-thermo-chemical regeneration approach which will generate a product solution containing hydroxyl ions for absorbing the flue gas CO2. This may work with existing flue gas desulfurizing equipment to minimize the cost of carbon capture. The process involves the use of low-cost make-up reagents which are capable of providing credits for partial mineralization of CO2, thus offsetting some of the costs for carbon capture and sequestration. The process presents the possibility of making this a low-cost on-site mineralization with cost offsets.

The role of minerals in biomass formation is understood only to a limited extent. When the term “photosynthesis—CO2 and H2O reduction of sugars, using solar energy”—is used, one normally thinks of chlorophyll as a compound containing magnesium. Alkali and alkaline earth metals present in leaf cells in the form of ions are equally essential in this solar energy bioconversion coupled with nitrogen fixation. Application of some of these principles can lead to artificial carbon-neutral processes on an industrial scale close to the concentrated CO2 emission sources.

The analysis of recently announced battery packs for plug-in hybrid electric vehicles (PHEV) shows that the design of the series-parallel combinations is being over-complicated. The proven energy densities of lithium-ion cells from about 200 Wh/kg are being reduced to 90 Wh/kg. The majority of the weight increase seems to be for thermal management. Simpler battery pack designs based on electro-refining pot rooms using self-contained rectangular lithium-ion cells with air cooling inside of die-cast magnesium cell tanks would help avoid hauling dead weight in PHEV by providing considerable weight reduction.

As an alternative to fossil fuels, solar energy can help minimize global warming triatomic gas emissions (CO2 and H2O) when used in metallurgical processes. This paper reviews the technical development in this field from the first patents filed in the late 1800s to present-day pilot work of solar zinc production.

To read more about them, turn to page 10. To join TMS, visit www.tms.org/Society/Membership.aspx. Energy conservation as well as CO 2 and other greenhouse gas reduction present long-term challenges to our society, and the problems are exacerbated by the rapid consumption of materials and energy and signifi cant emissions of greenhouse gas and toxic gases. By 2050 the world’s oil production will be half of what it is today. Capping CO 2 in the atmosphere at 450 ppmv will require its sequestration. Metallurgical industries and transportation systems are the main energy users and the main producers of greenhouse gas. Production of renewable energy and saving energy in metallurgical processing are two keys to energy conservation. As an example, solar cell energy is a well known renewable energy and it is claimed as a green energy by most people. However, if the feedstock, especially for multi-crystalline silicon, is included, solar cell energy is not a green energy since during the production of the high purity silicon, signifi cant energy is consumed, much CO 2 is emitted, and several non-green processes, such as strong acid leaching, are included. Furthermore, during the wafer slicing process of a high-purity silicon ingot, over 50% becomes slurry wastes and there are no successful industrial processes to recycle these valuable wastes. In order to save energy, traditional industrial processes should be optimized. Furthermore, reuse, recycling, and recovery of metals and materials should be emphasized since these processes usually use less energy than the primary production processes. The control of CO 2 and other greenEnergy Conservation, CO2, and Other Greenhouse Gas Reduction