6 research outputs found

    Operations sequencing in a cable assembly shop

    Get PDF
    The need for a better, compact and neat solution in the cable systems used by the automotive industry resulted in emerge of companies specialized in producing such cable systems. The present study is an extension of the work that was carried out for one such company. One of the main operations in the production of cable systems is the attachment of the connectors to the ends of the cables. This process is composed of cutting, stripping and crimping the cable ends. These operations are to be performed for each connecter attachment. Each connector type requires a different head for the crimping operation. Thus, the required setup time is doubled if the heads for both ends of the cable should be changed. The problem in hand is a TSP where the distances between the nodes are either one or two. An effective and simple heuristic algorithm is developed that yields either an optimum solution or one that is off by a few percent. Among nine experiments six resulted with optimum solution while the others deviated from the optimum at most one percent

    Detecting credit card fraud by genetic algorithm and scatter search

    No full text
    In this study we develop a method which improves a credit card fraud detection solution currently being used in a bank. With this solution each transaction is scored and based on these scores the transactions are classified as fraudulent or legitimate. In fraud detection solutions the typical objective is to minimize the wrongly classified number of transactions. However, in reality, wrong classification of each transaction do not have the same effect in that if a card is in the hand of fraudsters its whole available limit is used up. Thus, the misclassification cost should be taken as the available limit of the card. This is what we aim at minimizing in this study. As for the solution method, we suggest a novel combination of the two well known meta-heuristic approaches, namely the genetic algorithms and the scatter search. The method is applied to real data and very successful results are obtained compared to current practice

    A TSP (1,2) application arising in cable assembly shops

    No full text
    One of the main operations in producing cable systems in the automotive industry is that of cutting/stripping/crimping. The most time-consuming activity in this operation is changing the heads whenever a different connector is to be crimped at either one of the ends. This set-up time is practically doubled when the heads at both ends are to be changed. Thus, one is faced with the problem of minimizing the total machine set-up time; which turns out to be a TSP where the distances between the nodes are either one or two. A simple and effective heuristic algorithm is developed that yields solutions, which are only a few percent above the optimum in the worst case

    Improving a credit card fraud detection system using genetic algorithm

    No full text
    IĆŸÄ±k, Mine (Dogus Author) -- Duman, Ekrem (Dogus Author) -- Conference full title: 2010 International Conference on Networking and Information Technology, ICNIT 2010; Manila; Philippines; 11 June 2010 through 12 June 2010In this study we undertook the credit card fraud detection problem of a bank and tried to improve the performance of an existing solution. In doing so, we did not undertake the typical objective of maximizing the number of correctly classified transactions but rather we defined a new objective function where the misclassification costs are variable and thus, correct classification of some transactions are more important than correctly classifying the others. For this purpose we made an application of genetic algorithms which is a novel one in the related literature both in terms of the application domain and the cross-over operator used. The algorithm is applied to real life data where the savings obtained are almost three times the current practice

    Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

    Get PDF
    Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)
    corecore