The Experts below are selected from a list of 90363 Experts worldwide ranked by ideXlab platform
Christophe Rapine - One of the best experts on this subject based on the ideXlab platform.
-
Erratum to ''Johnson's algorithm : A key to solve optimally or approximately flowshop scheduling problems with unavailability periods'' [International Journal of Production Economics 121 (2009) 81-87]
International Journal of Production Economics, 2013Co-Authors: Christophe RapineAbstract:In Allaoui H., Artiba A, ''Johnson's algorithm : A key to solve optimally or approximately flowshop scheduling problems with unavailability periods'' [International Journal of Production Economics 121 (2009)] the authors propose optimality conditions for the Johnson sequence in presence of one unavailability period on the first machine and pretend for a performance guarantee of 2 when several unavailability periods may occur. We establish in this note that these conditions are false, and that minimizing the makespan in presence of more than one unavailability period is not in APX, unless P=NP. We also point out that the results given for the stochastic part of the problem are incorrect. Finally, we propose a simplified proof and a generalization for the two-stage hybrid flowshop.
-
Erratum to "Scheduling of a two-machine flowshop with availability constraints on the first machine" [International Journal of Production Economics 99 (2006)]
International Journal of Production Economics, 2013Co-Authors: Christophe RapineAbstract:In Allaoui H., Artiba A., Elmaghraby S.E., Riane F. Scheduling of a two-machine flowshop with availability constraints on the first machine. International Journal of Production Economics 99 (2006) two conditions of optimality for the Johnson sequence are given. We establish in this note that these conditions are false, under the resumable and the non-resumable case. We also point out two incorrect proofs and give evidence that the time complexity of their dynamic approach is very unlikely to be correct
-
Erratum to “Scheduling of a two-machine flowshop with availability constraints on the first machine” [International Journal of Production Economics 99 (2006) 16–27]
International Journal of Production Economics, 2013Co-Authors: Christophe RapineAbstract:Abstract In Allaoui H., Artiba A., Elmaghraby S.E., Riane F., 2006. Scheduling of a two-machine flowshop with availability constraints on the first machine. International Journal of Production Economics 99, 16–27, two conditions of optimality for the Johnson sequence are given. We establish in this note that these conditions are false, under the resumable and the non-resumable case. We also point out two incorrect proofs and give evidence that the time complexity of their dynamic approach is very unlikely to be correct.
-
Erratum to “Johnson's algorithm: A key to solve optimally or approximately flowshop scheduling problems with unavailability periods” [International Journal of Production Economics 121 (2009) 81–87]
International Journal of Production Economics, 2013Co-Authors: Christophe RapineAbstract:Abstract In Allaoui, H., Artiba, A., 2009. Johnson's algorithm: a key to solve optimally or approximately flowshop scheduling problems with unavailability periods. International Journal of Production Economics 121, 81–87, the authors propose optimality conditions for the Johnson sequence in the presence of one unavailability period on the first machine and pretend for a performance guarantee of 2 when several unavailability periods may occur. We establish in this note that these conditions are false, and that minimizing the makespan in the presence of more than one unavailability period is not in APX, unless P = NP . We also point out that the results given for the stochastic part of the problem are incorrect. Finally, we propose a simplified proof and a generalization for the two-stage hybrid flowshop.
R. Pd. Singh - One of the best experts on this subject based on the ideXlab platform.
-
Integration of Chemical and Manual Weed Management on Weed Density, Yield and Production Economics of Lentil (Lens culinaris Medikus)
International journal of Bio-resource and Stress Management, 2013Co-Authors: Jamkhogin Lhungdim, Y. Singh, R. Pd. SinghAbstract:Afield study was conducted during rabi, 2010–11 and 2011–12 atAgricultural Research farm, BHU, Varanasi (U.P.) where five herbicides either as sole, integrated with mechanical weeding (MW) or sequentially applied were evaluated for efficacies of the herbicides on controlling weeds, their influences on yield and Production Economics on lentil (Lens culinaris Medikus) variety HUL 57. Results revealed that, two hand weeding (HW) was the most effective method for weed control next to weed free. At 60 DAS however, lowest density and dry matter accumulation of all weed species were recorded with two hand weeding at 30 and 45 DAS followed by sequential/continuous application of Pendimethalin (PE) and Imazethapyr (post-emergence/POE) that remained statistically at par with Pendimethalin+MW in the case of BLWs and grasses and Chlorimuron ethyl+MW in respect of sedges. Maximum weed control efficiency (WCE) was achieved under two HW (83%) followed by Pendimethalin+MW at 45 DAS and continuous application of Pendimethalin+Imazethapyr (76% each). However, significantly highest yield (1365 kg ha−1), highest pods plant−1 (66.07), seeds pod−1 (1.94) and nodules plant−1 (8.20) were recorded under Pendimethalin+MW which was comparable and significantly not different from Pendimethalin+Imazethapyr @ 37.5 g a.i. ha−1. Among sole applications, Pendimethalin and Pendimethalin+Imazethapyr (pre-mixed) significantly suppressed broadleaved weeds but poorly controlled the sedges and grasses though it was better than control. In the economic factor, Pendimethalin+MW with highest net return and benefit:cost ratio ( 47521 ha−1 and 3.15) and lowest weed index (4.51) was comparatively better than all the treatments including control. This integrated treatment was found as the most profit-oriented and sustainable weed management system in lentil.
Tonya Boone - One of the best experts on this subject based on the ideXlab platform.
-
Production Economics and process quality a taguchi perspective
International Journal of Production Economics, 2001Co-Authors: Ram Ganeshan, Shailesh S Kulkarni, Tonya BooneAbstract:Abstract Although several studies have analyzed the interaction between the Economics of Production and process quality, most of them view quality from a very traditional perspective – reject when outside specified limits, or else accept. Recent views on quality have shown that such a definition greatly underestimates the costs of poor quality and leads to sub-optimal decisions. The primary intent in this paper is to revisit this interaction of the Economics of Production with process quality from a non-traditional yet more realistic “Taguchi” quality cost perspective. Specifically, we investigate the possibility of investing in a process to decrease its variance. Although such an investment reduces the proportion of defects, and when large enough, the Taguchi's loss, it also increases the cost of holding inventory. Our model determines the optimal levels of inventory, and the Production lot-size that minimizes the sum of inventory and quality-related costs.
Jamkhogin Lhungdim - One of the best experts on this subject based on the ideXlab platform.
-
Integration of Chemical and Manual Weed Management on Weed Density, Yield and Production Economics of Lentil (Lens culinaris Medikus)
International journal of Bio-resource and Stress Management, 2013Co-Authors: Jamkhogin Lhungdim, Y. Singh, R. Pd. SinghAbstract:Afield study was conducted during rabi, 2010–11 and 2011–12 atAgricultural Research farm, BHU, Varanasi (U.P.) where five herbicides either as sole, integrated with mechanical weeding (MW) or sequentially applied were evaluated for efficacies of the herbicides on controlling weeds, their influences on yield and Production Economics on lentil (Lens culinaris Medikus) variety HUL 57. Results revealed that, two hand weeding (HW) was the most effective method for weed control next to weed free. At 60 DAS however, lowest density and dry matter accumulation of all weed species were recorded with two hand weeding at 30 and 45 DAS followed by sequential/continuous application of Pendimethalin (PE) and Imazethapyr (post-emergence/POE) that remained statistically at par with Pendimethalin+MW in the case of BLWs and grasses and Chlorimuron ethyl+MW in respect of sedges. Maximum weed control efficiency (WCE) was achieved under two HW (83%) followed by Pendimethalin+MW at 45 DAS and continuous application of Pendimethalin+Imazethapyr (76% each). However, significantly highest yield (1365 kg ha−1), highest pods plant−1 (66.07), seeds pod−1 (1.94) and nodules plant−1 (8.20) were recorded under Pendimethalin+MW which was comparable and significantly not different from Pendimethalin+Imazethapyr @ 37.5 g a.i. ha−1. Among sole applications, Pendimethalin and Pendimethalin+Imazethapyr (pre-mixed) significantly suppressed broadleaved weeds but poorly controlled the sedges and grasses though it was better than control. In the economic factor, Pendimethalin+MW with highest net return and benefit:cost ratio ( 47521 ha−1 and 3.15) and lowest weed index (4.51) was comparatively better than all the treatments including control. This integrated treatment was found as the most profit-oriented and sustainable weed management system in lentil.
Marija Bogataj - One of the best experts on this subject based on the ideXlab platform.
-
Editorial: Special issue of the Sixteenth International Working Seminar on Production Economics, Innsbruck 2010
2012Co-Authors: Stephen Michael Disney, Marija Bogataj, Ou TangAbstract:This Special Issue includes a selection of papers which originally were presented and discussed at the Sixteenth International Working Seminar on Production Economics, Innsbruck, March 1–5, 2010 and subsequently extended and improved. Production Economics has a focus on scientific topics treating the interface between engineering, management and Economics. It therefore contains a wide range of subjects. The Working Seminar included sessions such as supply chain management, innovation management, general Production Economics, productivity and performance analysis, service management, risk management in Production, inventory control, scheduling, forecasting, simulation applications, green and reverse logistics, manufacturing strategy, Production planning and control, investment and financial planning. The Working Seminar had 216 participants from 26 countries. Its unique discussant system provides an excellent opportunity for participants to broader study horizons, exchange research ideas and improve research outcomes resulting in this special issue. The discussant system and the conference timetable create and promote the development of a unique Production Economics community.
-
Inventory allocation and customer travelling problem in spatial duopoly
International Journal of Production Economics, 1999Co-Authors: Marija BogatajAbstract:Abstract The paper is a theoretical study about connecting inventory allocation and market area for the goods, defined by customers’ travelling decisions, influenced by the expected shortages of goods. In the paper “Inventories in Spatial Models” (Bogataj, International Journal of Production Economics 45 (1996) 337–342 [2] ) we have emphasized the need for connecting inventory and location analysis. This problem was studied further by H.J. Girlich in his paper “On the Metric Transportation Problems and Their Solution” (Girlich, Lecture Notes of the International Postgraduate Summer School, vol. 2, 1995, pp. 13–24), which gives us proper foundations for our present research. The study is influenced by Grubbstrom and Molinder’s work on MRP optimization (for details see Grubbstrom, Management Science 13(7) (1967) 558–567; Grubbstrom, The Mathematical Scientist 16 (1991) 118–129; Grubbstrom, International Journal of Production Economics, forthcoming; Grubbstrom, International Encyclopaedia of Business and Management, 1996; Grubbstrom and Molinder, Proceedings of the Eight International Working Seminar on Production Economics, 1994; Grubbstrom and Molinder, International Journal of Production Economics 35 (1994) 299–31 [6–11] ). The annuity stream approach has been applied in the environment of spatial duopoly, where the optimal ordering policy depends on the interaction between the prices and shortages of goods in the studied duopolies. Customer travelling problem (CTP) is defined, which determines the market area for allocated inventories.
