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Related Procedures (relate + procedure)

Distribution by Scientific Domains

Medical Sciences	50%

Selected Abstracts

SOLVING DYNAMIC WILDLIFE RESOURCE OPTIMIZATION PROBLEMS USING REINFORCEMENT LEARNING

NATURAL RESOURCE MODELING, Issue 1 2005
CHRISTOPHER J. FONNESBECK
ABSTRACT. An important technical component of natural resource management, particularly in an adaptive management context, is optimization. This is used to select the most appropriate management strategy, given a model of the system and all relevant available information. For dynamic resource systems, dynamic programming has been the de facto standard for deriving optimal state-specific management strategies. Though effective for small-dimension problems, dynamic programming is incapable of providing solutions to larger problems, even with modern microcomputing technology. Reinforcement learning is an alternative, related procedure for deriving optimal management strategies, based on stochastic approximation. It is an iterative process that improves estimates of the value of state-specific actions based in interactions with a system, or model thereof. Applications of reinforcement learning in the field of artificial intelligence have illustrated its ability to yield near-optimal strategies for very complex model systems, highlighting the potential utility of this method for ecological and natural resource management problems, which tend to be of high dimension. I describe the concept of reinforcement learning and its approach of estimating optimal strategies by temporal difference learning. I then illustrate the application of this method using a simple, well-known case study of Anderson [1975], and compare the reinforcement learning results with those of dynamic programming. Though a globally-optimal strategy is not discovered, it performs very well relative to the dynamic programming strategy, based on simulated cumulative objective return. I suggest that reinforcement learning be applied to relatively complex problems where an approximate solution to a realistic model is preferable to an exact answer to an oversimplified model. [source]

Do Country Specific Bankruptcy Codes Determine Long-term Financial Performance?

JOURNAL OF INTERNATIONAL FINANCIAL MANAGEMENT & ACCOUNTING, Issue 2 2001
Columbia Gas System, The Case of Metallgesellschaft AG
In this paper, we examine the impact of financial distress, the bankruptcy code, and related procedures on the long-term performance of two companies engaged in similar businesses across two countries. Both the companies were driven into bankruptcy as a result of unanticipated changes in energy prices. Though the resolution of bankruptcy of the US firm took a longer time, the post-reorganization performance of the firm has been excellent. In contrast, the post-reorganization performance of the German firm, which emerged out of bankruptcy in 2 weeks, has been poor. These results are consistent with the view that one of the important determinants of post-bankruptcy performance of a firm is more likely to be the underlying economic fundamentals rather than the country specific bankruptcy code through which the firm reorganizes. [source]

Classification for coding procedures in the intensive care unit

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 8 2002
H. Flaatten
Background: There is no commonly accepted coding system for non-operative procedures in general, including intensive care unit (ICU) procedures. In order to create a classification of codes for ICU procedures, a system developed at the University Hospital of Bergen was evaluated in four Nordic countries. Methods: Classification codes were constructed using seven main groups of related procedures that were given a letter from A to G. Within each group major procedures were given a number from 00 to 99, with the possibility of up to 10 subclassifications within each procedure. A simple questionnaire regarding the use of coding general ICU procedures and some specific procedures was sent to 171 ICUs in Sweden, Finland, Denmark, and Norway. They were also asked to give their comments on the new classification coding system, which was attached. Results: One hundred and fifty-four questionnaires were returned (response rate 90%). Some or most of the ICU procedures were registered in the ICUs (82.2%). However 38% did not use any coding system and 24% used a specific internal system. The new classification coding system was well received, and was given a mean value of 7.5 using a VAS scale from 0 to 10 (best). Most ICUs would consider using this system if introduced at a national level. Conclusion: Most Nordic ICUs do register some or most of the procedures performed. Such procedures are however, registered in very different ways, using several different systems, and are often home-made. The new classification system of ICU procedures was well rated. [source]

Hypospadias surgery: when, what and by whom?

BJU INTERNATIONAL, Issue 8 2004
Gianantonio Manzoni
Summary Hypospadias is repaired by paediatric surgeons, paediatric urologists, adult reconstructive urologists and plastic surgeons. This review is unique in representing all four specialities, to provide a unified policy on the management of hypospadias. The surgeon of whichever speciality should have a dedicated interest in this challenging work, ideally having an annual volume of at least 40,50 cases. The ideal time for primary repair is at 6,12 months old, although when this is not practicable there is another opportunity at 3,4 years old. A surgical protocol is presented which emphasises both functional and cosmetic refinement. Using a logical progression of a very few related procedures allows the reliable correction of almost any hypospadias deformity. A one-stage repair is used when the urethral plate does not require transection and its axial integrity can be maintained. Occasionally, when the plate is of adequate width and depth, it can be tubularized directly using the second stage of the two-stage repair. When (usually) the urethral plate is not adequately developed and requires augmentation before it can be tubularized, then that second-stage procedure is modified by adding a dorsal releasing incision ± a graft (alias Snodgrass and ,Snodgraft' procedures). The two-stage repair offers the most reliable and refined solution for those patients who require transection of the urethral plate and a full circumferential substitution urethroplasty. From available evidence this protocol combines excellent function and cosmesis with optimum reliability. Nevertheless, it would be complacent to assume that these gratifying results will be maintained into adult life. We therefore recommend that there is still a need for active follow-up through to genital maturity. [source]