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System Cost (system + cost)
Selected AbstractsDesign and Management Strategies for Mixed Public Private Transportation Networks: A Meta-Heuristic ApproachCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2009Avinash Unnikrishnan In this study, private companies are assumed to have a degree of control over highway sections on which they perform maintenance and rehabilitation and capacity expansion activities. The private investors recover the cost of construction by levying tolls. The public agency is assumed to maintain the rest of the network with the objective of minimizing total system generalized cost. The bi-directional impact of roadway utilization on deterioration and deterioration on utilization is modeled in this study. The model accounts for route choice of users and all users are assumed to choose routes that have equal and minimal experienced generalized cost. The nonconvex and discontinuous multi-objective mathematical program is solved using nondominant sorting genetic algorithm-II and the pareto-optimal trade-off surface between the profit of the private company and the total system cost is generated. Computational runs are conducted to demonstrate the suitability and flexibility of the developed framework in modeling various policy decisions such as the presence of noncompete clauses. [source] Evaluation of cost and reliability of power systems with large numbers of distributed generatorsELECTRICAL ENGINEERING IN JAPAN, Issue 2 2009Yutaka Sasaki Abstract The authors have proposed the Flexible, Reliable and Intelligent ENergy Delivery System (called "FRIENDS"), which is a new concept for future power distribution systems. Also, a "micro grid" which is a similar concept to FRIENDS has been developed. In a micro grid, an independent distribution system can be constituted by a number of distributed generators. In this paper, FRIENDS, Micro grid, and conventional distribution systems are compared quantitatively in supply reliability and system cost through time sequential Monte Carlo simulations. In addition, for cost evaluation, interruption costs are included to show risk incurred by unsupplied energy. Finally, the authors search for preferable form with install and operation of distributed generators and network composition according to social cost including interruption cost and system cost. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(2): 28,37, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20659 [source] New centralized automatic vehicle location communications software system under GIS environmentINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 9 2005Omar Al-Bayari Abstract Recent advances in wireless communications and networks have integrated relatively new technologies such as Global Positioning System (GPS), to the popular Global System for Mobile Communication (GSM), second generation cellular systems and the Geographic Information Systems (GIS) technologies. Automatic Vehicle Location (AVL) is based on a combination of GPS, GIS and telecommunication technologies. Automatic Vehicle Tracking systems are more and more used for different purposes, especially those related to tracking one vehicle or a fleet of vehicles. In this work, we introduce a new AVL system, which is based and developed under GIS software environment. The centralized software at the control station offers a new technology of transferring the intelligence of tracking system from the car unit, into the control office PC software. Centralized software will reduce the programming efforts in the car unit and will offer better fleet management. Moreover, the core of our system is based on the objects or the controllers of the GIS software, which reduces dramatically the overall system cost. Our system provides an easy access to change the functions of the system, with great possibility to satisfy the local needs. The design of our software will be presented with an explanation of the new supporting technologies that were to create the system. Finally, our software system has been validated using data from local road networks. Copyright © 2005 John Wiley & Sons, Ltd. [source] Sensitivity analysis of investments in the pulp and paper industry On investments in the chemical recovery cycle at a board millINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 14 2002M. Karlsson Abstract In the pulp and paper industry, energy costs represents a relatively large proportion of the value of production. When investing in new equipment, considerations concerning boundary conditions, such as electricity and oil prices, are therefore of great importance. A vital requirement is the identification of other key parameters influencing production costs as well as possible interaction between these parameters. In this paper, a sensitivity analysis is accomplished by using an optimization model that minimizes the system cost combined with a systematic approach involving a statistical method. The paper analyses the possibilities of investing in a new chemical recovery cycle, including a new recovery boiler and evaporation plant, at a Swedish board mill. The study includes a survey of future changes, together with forecasts of boundary conditions, such as changes in the price of electricity and oil. Interactions between different parameters are also examined. Copyright © 2002 John Wiley & Sons, Ltd. [source] An integrated inventory model with controllable lead time and distribution-free demandAPPLIED STOCHASTIC MODELS IN BUSINESS AND INDUSTRY, Issue 4 2010Shu-Lu Hsu Abstract The impact of lead time reduction on an integrated periodic review inventory system comprising a single vendor and multiple buyers with a step crashing cost function and service-level constraints is studied. The probability distribution of demand during the protection period for each buyer is unknown, but the mean and the variance are given. Each production lot of the vendor can be delivered in a number of shipments to all buyers. A minimax distribution-free procedure with Lagrange multipliers is applied to determining the lead time, the common shipment cycle time, the target levels of replenishments and the number of shipments per production cycle so that the expected total system cost is minimized. Numerical experiments along with sensitivity analysis were performed to illustrate the effects of parameters on the decision and the total system cost. Copyright © 2009 John Wiley & Sons, Ltd. [source] Obesity,hypertension: an ongoing pandemicINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 2 2007E. A. Francischetti Summary Considerable evidence has suggested that excessive weight gain is the most common cause of arterial hypertension. This association has been observed in several populations, in different regions of the world. Obesity,hypertension, a term that underscores the link between these two deleterious conditions, is an important public health challenge, because of its high frequency and concomitant risk of cardiovascular and kidney diseases. The obesity,hypertension pandemic imposes a considerable economic burden on societies, directly reflecting on healthcare system costs. Increased renal sodium reabsorption and blood volume expansion are central features in the development of obesity,hypertension. Overweight is also associated with increased sympathetic activity. Leptin, a protein expressed in and secreted by adipocytes, is the main factor linking obesity, increased sympathetic nervous system activity and hypertension. The renin,angiotensin,aldosterone system has also been causally implicated in obesity,hypertension, because angiotensinogen is expressed in and secreted by adipose tissue. Hypoadiponectinemia, high circulating levels of free fatty acids and increased vascular production of endothelin-1 (ET-1) have been reported as potential mechanisms for obesity,hypertension. Lifestyle changes are effective in obesity,hypertension control, though pharmacological treatment is frequently necessary. Despite the consistency of the mechanistic approach in explaining the causal relation between hypertension and obesity, there is yet no evidence that one class of drug is superior to the others in controlling obesity,hypertension. In this review, we present the current knowledge and research in obesity,hypertension, exploring the epidemiologic evidence of the association, its probable pathophysiological mechanisms and treatment issues. [source] Parking difficulty and parking information system technologies and costsJOURNAL OF ADVANCED TRANSPORTATION, Issue 2 2008Hualiang (Harry) Teng Before the implementation of a parking information system, it is necessary to evaluate the parking difficulty, technology choice, and system costs. In this study, the parking problem was quantified by asking parkers to express their parking difficulties in five scaled levels from the least to the most difficult. An ordered Probit model was developed to identify the factors that influence a parker to feel the parking difficulty. The results indicate that the amount of parking information parkers had before their trips was directly related to their parking search time, which in turn, influenced their perceptions of parking difficulty. Parkers' preferences to parking information technologies were identified based on developing binary and multinomial probit models. The results indicate that personal business trips and older persons would like to use the kiosk, while the more educated and males would not. Trips with shopping and social/recreation purposes and the drivers who had visited the destination areas frequently would like to choose roadside display. Drivers who had planned their parking and had Internet access would use in-vehicle device. The system cost was estimated based on the cost for each component of the system. The results show that providing en-route parking search information through roadside displays is more expensive than providing pre-trip information through a web site. [source] Hospital system costs of artificial infant feeding: estimates for the Australian Capital TerritoryAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 6 2002Julie P. Smith Objective: To estimate the attributable ACT hospital system costs of treating selected infant and childhood illnesses having known associations with early weaning from human milk. Method: We identified relative risks of infant and childhood morbidity associated with exposure to artificial feeding in the early months of life vs breastfeeding from cohort studies cited by the American Academy of Pediatrics in 1997 as establishing the protective effect of breastfeeding. Data for ACT breastfeeding prevalence is assessed from a 1997 prospective population-based cohort study of 1,295 women. ACT Hospital Morbidity Data and DRG treatment costs were used to estimate the attributable fraction of costs of hospitalisation for gastrointestinal illness, respiratory illness and otitis media, eczema, and necrotising enterocolitis. Results: Although initiation rates were high (92%), less than one in 10 ACT infants are exclusively breastfed for the recommended six months, mainly due to supplementation or weaning on to formula within the first three months and the early introduction of solids by breastfeeding mothers. This study suggests the attributable hospitalisation costs of early weaning in the ACT are about $1 -2 million a year for the five illnesses. Conclusions and implications: Early weaning from breast milk is associated with significant hospital costs for treatment of gastrointestinal illness, respiratory illness and otitis media, eczema, and necrotising enterocolitis These costs are minimum estimates of the cost of early weaning as they exclude numerous other chronic or common illnesses and out-of-hospital health care costs. Higher rates of exclusive breastfeeding would reduce these costs. Interventions to protect and support breastfeeding are likely to be cost-effective for the public health system. [source] Klimapolitik: Kyoto-Protokoll und Emissionshandel für CO2 -Zertifikate in der EU1PERSPEKTIVEN DER WIRTSCHAFTSPOLITIK, Issue 3 2005Wolfgang Ströbele Also every economist knows that the institutional conditions and the rules of the game are important. This basic idea stood behind the introduction of a CO2 -emissions trading system within the European Community starting in 2005. Since the starting point is the Kyoto-protocol with its subset of relevant states involved and the rules agreed upon there, one must ask whether the EU CO2-trading system is really an instrument that helps to reach the Kyoto goals more efficiently. A positive answer to this question is very doubtful. The new European subsystem is only valid for CO2 while Kyoto knows six greenhouse gases, the EU trading periods are 2005,2007 and 2008,2012 while Kyoto is only relevant for the second period, the integration with all flexible instruments of Kyoto is not guaranteed from the beginning. The plants involved are power plants and plants with high energy intensity. Since the technological levels of these plants are rather similar in Europe, the difference in marginal abatement cost will not be large enough to offset the rather high transaction cost of the special EU system. Furthermore, the heating systems and small scale plants of industry are not included in the trading system. The same holds true for traffic, households and the service sector. Drawing a borderline between CO2 -policy there and the trading activities will cause inefficiencies. If CO2 -prices are high, the main incentive of the trading system will be a large shift from domestic production to production abroad without any CO2 -restrictions. Leakage-effects will then be dominant. With low CO2 -prices the special European bureaucratic system will not create enough efficiency gains to cover the trading system's cost. [source] The Impact of E-Replenishment Strategy on Make-to-Order Supply Chain PerformanceDECISION SCIENCES, Issue 1 2005E. Powell Robinson Jr. ABSTRACT This research investigates the impact of electronic replenishment strategy on the operational activities and performance of a two-stage make-to-order supply chain. We develop simulation-based rolling schedule procedures that link the replenishment processes of the channel members and apply them in an experimental analysis to study manual, semi-automated, and fully automated e-replenishment strategies in decentralized and coordinated decision-making supply chain structures. The average operational cost reductions for moving from a manual-based system to a fully automated system are 19.6, 29.5, and 12.5%, respectively, for traditional decentralized, decentralized with information sharing, and coordinated supply chain structures. The savings are neither equally distributed among participants, nor consistent across supply chain structures. As expected, for the fully coordinated system, total costs monotonically decrease with higher levels of automation. However, for the two decentralized structures, under which most firms operate today, counter-intuitive findings reveal that the unilateral application of e-procurement technology by the buyer may lower his purchasing costs, but increase the seller's and system's costs. The exact nature of the relationship is determined by the channel's operational flexibility. Broader results indicate that while the potential economic benefit of e-replenishment in a decentralized system is substantial, greater operational improvements maybe possible through supply chain coordination. [source] Evaluation of the Utah Student Injury Reporting SystemJOURNAL OF SCHOOL HEALTH, Issue 2 2002Rebecca S. Spicer ABSTRACT: The Utah Student Injury Reporting System (SIRS), implemented in 1984 to monitor injuries to students in grades K-12 in Utah schools, has served as a model for surveillance systems created by other states and some European countries. This paper evaluates the Utah experience in developing and administering the SIRS. The evaluation identifies usefulness of the system, discusses the sensitivity of the system in detecting school injuries, estimates the system's costs, and provides suggestions to other states and districts interested in building a cost-effective and efficient surveillance instrument. (J Sch Health. 2002;72(2):47-50) [source] | ||||||||||||||||