scholarly journals A Joint Production and Maintenance Optimization of Closed-Loop Production System under Carbon Emission with a Switching Subcontractor Consideration

2019 ◽  
Vol 9 (6) ◽  
pp. 1105 ◽  
Author(s):  
Zied Hajej ◽  
Nidhal Rezg ◽  
Salim Bouslikhane

This study outlines a new forecasting problem of closed-loop production system under environmental aspect by proposing a new solution based on subcontracting. By studying the impact of the carbon tax on decision-making of production optimization, we propose an original economic production and maintenance strategies to minimize the total cost. Additionally, to reduce the total quantity of carbon and its tax, the subcontractor has a role to help either manufacturing or remanufacturing unit during the process of production. Indeed, the principle objectives are to determine the economic production plans for manufacturing, remanufacturing and subcontracting units as well as the optimal maintenance planning characterized by the optimal number of preventive maintenance actions for manufacturing unit, minimizing the total cost of production, inventory, carbon penalty and maintenance.

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
N. Li ◽  
Felix T. S. Chan ◽  
S. H. Chung ◽  
Allen H. Tai

This paper investigates the economic production quantity model jointly considering product deterioration and a deteriorating production system with rework. In this imperfect deteriorating production system, not only does the machine produce defective product but also the machine is subjected to quality deterioration. To be more specific, the defective rate increases at certain time intervals. The defects produced are stored until the end of normal production process. Then they are reworked with extra cost to restore their quality and regarded as perfect product. The main objective is to minimize the total cost per unit product by determining the optimal combination of production run time and backlog quantity. Numerical experiments are carried out to illustrate the behavior of the inventory and show the impact of different parameters on the model. Discussion and conclusions are made at the end of the paper.


2020 ◽  
Vol 13 (37) ◽  
pp. 3850-3870
Author(s):  
Pratiksha Saxena ◽  

Background/Objectives: To trim down the recycling cost of any manufactured goods with the help of green design and product stewardship. Methods/Statistical analysis: For the planned EPQ (economic production quantity model) model, all costs are calculated to find total cost and this total cost is optimized with the help of the Hessian matrix. Sensitivity analysis is also carried w.r.t. different parameters, to illustrate the impact of these parameters on the proposed model. The convexity of the total cost function is also checked with the help of mathematical software Mathematica 9.0. Findings: Major finding of the proposed model are as follows: (i) Increase in the number of recycles results in the reduction of the total cost. (ii) Product stewardship parameter has a negative effect on total cost as the PS increases from 1 to 4 units, total cost decreases from 5926.00 to 5918.96 units (see Table 9 ) (similar findings can be written for numeric example 1 after correcting it). (iii) Green design costs have a positive effect on total cost, as the green design cost increases from 3 to 6 units, total cost also increases from 5918.49 to 5920.37 units (see Table 10 ). (iv) increase in the number of recycles results in the reduction of the total cost, as the number of recycles increases from 20 to 50 units total cost decreases from 5922.87 to 5919.12 units (see Table 11 ). Novelty/Applications: The Study of the effects of recycling by this green design and product stewardship approach makes the proposed model distinctive from the existing methods. The proposed model applies to eco-friendly manufacturing items with green design and product stewardship. Keywords: Green design; product stewardship; production model; own warehouse (OW); rented warehouse (RW); shortage; deterioration


2012 ◽  
Vol 241-244 ◽  
pp. 1503-1506 ◽  
Author(s):  
Hong Wei Jiang

This paper establishes a two-period production optimization model of the closed-loop supply chain with remanufacturing incorporating the consumers’ different preferences for the new product and the remanufactured product. Through theoretical analysis, we obtain the optimum production and pricing strategies, and analyze the impact of the consumers’ acceptance for the remanufactured product on production quantity and product pricing, which provides a basis for the manufacturer’s production decisions.


2012 ◽  
Vol 220 (1) ◽  
pp. 3-9 ◽  
Author(s):  
Sandra Sülzenbrück

For the effective use of modern tools, the inherent visuo-motor transformation needs to be mastered. The successful adjustment to and learning of these transformations crucially depends on practice conditions, particularly on the type of visual feedback during practice. Here, a review about empirical research exploring the influence of continuous and terminal visual feedback during practice on the mastery of visuo-motor transformations is provided. Two studies investigating the impact of the type of visual feedback on either direction-dependent visuo-motor gains or the complex visuo-motor transformation of a virtual two-sided lever are presented in more detail. The findings of these studies indicate that the continuous availability of visual feedback supports performance when closed-loop control is possible, but impairs performance when visual input is no longer available. Different approaches to explain these performance differences due to the type of visual feedback during practice are considered. For example, these differences could reflect a process of re-optimization of motor planning in a novel environment or represent effects of the specificity of practice. Furthermore, differences in the allocation of attention during movements with terminal and continuous visual feedback could account for the observed differences.


Author(s):  
M. Novokhatskyi ◽  
◽  
V. Targonya ◽  
T. Babinets ◽  
O. Gorodetskyi ◽  
...  

Aim. Assessment of the impact of the most common systems of basic tillage and biological methods of optimization of nutrition regimes on the realization of the potential of grain productivity of soybean in the Forest-Steppe of Ukraine. Methods. The research used general scientific (hypothesis, experiment, observation) and special (field experiment, morphological analysis) methods Results. The analysis of the results of field experiments shows that the conservation system of soil cultivation, which provided the formation of 27.6 c/ha of grain, is preferable by the level of biological yield of soybean. The use of other systems caused a decrease in the biological yield level: up to 26.4 c/ha for the use of the traditional system, up to 25.3 c/ha for the use of mulching and up to 23.0 c/ha for the use of the mini-till. With the use of Groundfix, the average biological yield of soybean grain increases to 25.6 c / ha for application rates of 5 l/ha, and to 28.2 c/ha for application rates of 10 l/ha when control variants (without the use of the specified preparation) an average of 22.6 c/ha of grain was formed with fluctuations in soil tillage systems from 21.0 (mini-bodies) to 25.8 c/ha (traditional).The application of Groundfix (10 l/ha) reduced the seed abortion rate from 11.0% (average without biofertilizer variants) to 8.0%, forming the optimal number of stem nodes with beans, increasing the attachment height of the lower beans and improving other indicators of biological productivity soybeans. Conclusions. It has been found that the use of the canning tillage system generates an average of 27.6 cent soybean grains, which is the highest indicator among the main tillage systems within the scheme of our research. The use of Groundfix caused a change in this indicator: if the variants with a conservative system of basic tillage without the use of biological preparation (control) were formed on average 24.1 c/ha, the use of Ground Licks caused the increase of biological productivity up to 29.4 c/ha, and at a dose of 10 l/ha biological yield was 32.2 c/ha. It was found that both the use of Groundfix and the basic tillage system influenced the elements of the yield structure: the density of the plants at the time of harvest depended more on the tillage system than on the use of Groundfix; the use of Groundfix and increasing its dose within the scheme of our studies positively reflected on the density of standing plants; the height of attachment of the lower beans and reduced the abortion of the seeds.


2019 ◽  
Vol 6 (1) ◽  
pp. 48-50
Author(s):  
Ikram Uddin

This study will explain the impact of China-Pak Economic Corridor (CPEC) on logistic system of China and Pakistan. This project is estimated investment of US $90 billion, CPEC project is consists of various sub-projects including energy, road, railway and fiber optic cable but major portion will be spent on energy. This project will start from Kashgar port of china to Gwadar port of Pakistan. Transportation is sub-function of logistic that consists of 44% total cost of logistic system and 20% total cost of production of manufacturing and mainly shipping cost and transit/delivery time are critical for logistic system. According to OEC (The Observing Economic Complexity) currently, china is importing crude oil which 13.4% from Persian Gulf. CPEC will china for lead time that will be reduced from 45 days to 10 days and distance from 2500km to 1300km. This new route will help to china for less transit/deliver time and shipping cost in terms of logistic of china. Pakistan’s transportation will also improve through road, railway and fiber optic cabal projects from Karachi-Peshawar it will have speed 160km per hour and with help of pipeline between Gwadar to Nawabshah gas will be transported from Iran. According to (www.cpec.inf.com) Pakistan logistic industry will grow by US $30.77 billion in the end of 2020.


2019 ◽  
Vol 24 (6) ◽  
pp. 722-727
Author(s):  
Aladine A. Elsamadicy ◽  
Andrew B. Koo ◽  
Megan Lee ◽  
Adam J. Kundishora ◽  
Christopher S. Hong ◽  
...  

OBJECTIVEIn the past decade, a gradual transition of health policy to value-based healthcare has brought increased attention to measuring the quality of care delivered. In spine surgery, adolescents with scoliosis are a population particularly at risk for depression, anxious feelings, and impaired quality of life related to back pain and cosmetic appearance of the deformity. With the rising prevalence of mental health ailments, it is necessary to evaluate the impact of concurrent affective disorders on patient care after spinal surgery in adolescents. The aim of this study was to investigate the impact that affective disorders have on perioperative complication rates, length of stay (LOS), and total costs in adolescents undergoing elective posterior spinal fusion (PSF) (≥ 4 levels) for idiopathic scoliosis.METHODSA retrospective study of the Kids’ Inpatient Database for the year 2012 was performed. Adolescent patients (age range 10–17 years old) with AIS undergoing elective PSF (≥ 4 levels) were selected using the International Classification of Diseases, Ninth Revision, Clinical Modification coding system. Patients were categorized into 2 groups at discharge: affective disorder or no affective disorder. Patient demographics, comorbidities, complications, LOS, discharge disposition, and total cost were assessed. The primary outcomes were perioperative complication rates, LOS, total cost, and discharge dispositions.RESULTSThere were 3759 adolescents included in this study, of whom 164 (4.4%) were identified with an affective disorder (no affective disorder: n = 3595). Adolescents with affective disorders were significantly older than adolescents with no affective disorders (affective disorder: 14.4 ± 1.9 years vs no affective disorder: 13.9 ± 1.8 years, p = 0.001), and had significantly different proportions of race (p = 0.005). Aside from hospital region (p = 0.016), no other patient- or hospital-level factors differed between the cohorts. Patient comorbidities did not differ significantly between cohorts. The number of vertebral levels involved was similar between the cohorts, with the majority of patients having 9 or more levels involved (affective disorder: 76.8% vs no affective disorder: 79.5%, p = 0.403). Postoperative complications were similar between the cohorts, with no significant difference in the proportion of patients experiencing a postoperative complication (p = 0.079) or number of complications (p = 0.124). The mean length of stay and mean total cost were similar between the cohorts. Moreover, the routine and nonroutine discharge dispositions were also similar between the cohorts, with the majority of patients having routine discharges (affective disorder: 93.9% vs no affective disorder: 94.9%, p = 0.591).CONCLUSIONSThis study suggests that affective disorders may not have a significant impact on surgical outcomes in adolescent patients undergoing surgery for scoliosis in comparison with adults. Further studies are necessary to elucidate how affective disorders affect adolescent patients with idiopathic scoliosis, which may improve provider approach in managing these patients perioperatively and at follow-up in hopes to better the overall patient satisfaction and quality of care delivered.


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