scholarly journals Planning Annual LNG Deliveries with Transshipment

Energies ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1490
Author(s):  
Mingyu Li ◽  
Peter Schütz
Keyword(s):  
Storage Capacity ◽  
Computational Time ◽  
Planning Problem ◽  
Rolling Horizon ◽  
Solution Quality ◽  
Total Cost ◽  
New Variant ◽  
Solution Methods ◽  
Time Formulation ◽  
The Impact

The introduction of transshipment ports in the liquefied natural gas (LNG) supply chain in recent years offers additional flexibility, but also challenges to the planning of the annual delivery program. We present a new variant of the LNG-annual delivery program (ADP) planning problem by considering transshipment as well as time-dependent sailing times. We present a continuous time formulation for the LNG-ADP problem and propose a rolling horizon heuristic to solve the problem. Both the model and heuristic were used to solve a case inspired by the Yamal LNG project. The computational results show that the heuristic provides good solutions within a relatively short amount of time, especially compared to the exact solution methods. However, there is a trade-off between computational time and solution quality when designing the rolling horizon heuristic. The results also show the impact storage capacity at the transshipment port has on the total cost.

A Non-Dominant Sorting Genetic Algorithm for Optimization of a Product Design and Selection of Its Suppliers

2020 ◽  
Vol 19 (01) ◽  
pp. 167-188
Author(s):  
Oulfa Labbi ◽  
Abdeslam Ahmadi ◽  
Latifa Ouzizi ◽  
Mohammed Douimi
Keyword(s):  
Genetic Algorithm ◽  
Product Design ◽  
Computational Time ◽  
Optimization Approach ◽  
Nsga Ii ◽  
Solution Quality ◽  
Holding Costs ◽  
Weighted Sum Method ◽  
The Impact ◽  
Selection Of

The aim of this paper is to address the problem of supplier selection in a context of an integrated product design. Indeed, the product specificities and the suppliers’ constraints are both integrated into product design phase. We consider the case of improving the design of an existing product and study the selection of its suppliers adopting a bi-objective optimization approach. Considering multi-products, multi-suppliers and multi-periods, the mathematical model proposed aims to minimize supplying, transport and holding costs of product components as well as quality rejected items. To solve the bi-objective problem, an evolutionary algorithm namely, non-dominant sorting genetic algorithm (NSGA-II) is employed. The algorithm provides a set of Pareto front solutions optimizing the two objective functions at once. Since parameters values of genetic algorithms have a significant impact on their efficiency, we have proposed to study the impact of each parameter on the fitness functions in order to determine the optimal combination of these parameters. Thus, a number of simulations evaluating the effects of crossover rate, mutation rate and number of generations on Pareto fronts are presented. To evaluate performance of the algorithm, results are compared to those obtained by the weighted sum method through a numerical experiment. According to the computational results, the non-dominant sorting genetic algorithm outperforms the CPLEX MIP solver in both solution quality and computational time.

The ROLE OF CHINA-PAK ECONOMIC CORRIDOR (CPEC) IN LOGISTIC SYSTEM OF PAKISTAN’S AND CHINA’S

2019 ◽  
Vol 6 (1) ◽  
pp. 48-50
Author(s):  
Ikram Uddin
Keyword(s):  
Persian Gulf ◽  
Lead Time ◽  
Fiber Optic ◽  
Delivery Time ◽  
Fiber Optic Cable ◽  
Total Cost ◽  
Economic Complexity ◽  
Shipping Cost ◽  
The Impact

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.

Reduced influence of affective disorders on perioperative complication rates, length of hospital stay, and healthcare costs following spinal fusion for adolescent idiopathic scoliosis

2019 ◽  
Vol 24 (6) ◽  
pp. 722-727
Author(s):  
Aladine A. Elsamadicy ◽  
Andrew B. Koo ◽  
Megan Lee ◽  
Adam J. Kundishora ◽  
Christopher S. Hong ◽  
...  
Keyword(s):  
Quality Of Care ◽  
Idiopathic Scoliosis ◽  
Affective Disorder ◽  
Affective Disorders ◽  
Complication Rates ◽  
Total Cost ◽  
Adolescent Patients ◽  
Perioperative Complication ◽  
The Impact

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.

scholarly journals Model-Based Control of Torque and Nitrogen Oxide Emissions in a Euro VI 3.0 L Diesel Engine through Rapid Prototyping

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1107
Author(s):  
Stefano d’Ambrosio ◽  
Roberto Finesso ◽  
Gilles Hardy ◽  
Andrea Manelli ◽  
Alessandro Mancarella ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Rapid Prototyping ◽  
Nitrogen Oxide ◽  
Thermal State ◽  
Pollutant Emissions ◽  
Computational Time ◽  
Nox Emissions ◽  
Model Based ◽  
Brake Mean Effective Pressure ◽  
The Impact

In the present paper, a model-based controller of engine torque and engine-out Nitrogen oxide (NOx) emissions, which was previously developed and tested by means of offline simulations, has been validated on a FPT F1C 3.0 L diesel engine by means of rapid prototyping. With reference to the previous version, a new NOx model has been implemented to improve robustness in terms of NOx prediction. The experimental tests have confirmed the basic functionality of the controller in transient conditions, over different load ramps at fixed engine speeds, over which the average RMSE (Root Mean Square Error) values for the control of NOx emissions were of the order of 55–90 ppm, while the average RMSE values for the control of brake mean effective pressure (BMEP) were of the order of 0.25–0.39 bar. However, the test results also highlighted the need for further improvements, especially concerning the effect of the engine thermal state on the NOx emissions in transient operation. Moreover, several aspects, such as the check of the computational time, the impact of the controller on other pollutant emissions, or on the long-term engine operations, will have to be evaluated in future studies in view of the controller implementation on the engine control unit.

scholarly journals The Impact on Infectivity and Neutralization Efficiency of SARS-CoV-2 Lineage B.1.351 Pseudovirus

Viruses ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 633
Author(s):  
Yeong Jun Kim ◽  
Ui Soon Jang ◽  
Sandrine M. Soh ◽  
Joo-Youn Lee ◽  
Hye-Ra Lee
Keyword(s):  
South Africa ◽  
Monoclonal Antibodies ◽  
Cell Fusion ◽  
Receptor Binding ◽  
Neutralizing Antibodies ◽  
Receptor Binding Domain ◽  
Viral Spread ◽  
New Variant ◽  
Global Concern ◽  
The Impact

A new variant of SARS-CoV-2 B.1.351 lineage (first found in South Africa) has been raising global concern due to its harboring of multiple mutations in the spike that potentially increase transmissibility and yield resistance to neutralizing antibodies. We here tested infectivity and neutralization efficiency of SARS-CoV-2 spike pseudoviruses bearing particular mutations of the receptor-binding domain (RBD) derived either from the Wuhan strains (referred to as D614G or with other sites) or the B.1.351 lineage (referred to as N501Y, K417N, and E484K). The three different pseudoviruses B.1.351 lineage related significantly increased infectivity compared with other mutants that indicated Wuhan strains. Interestingly, K417N and E484K mutations dramatically enhanced cell–cell fusion than N501Y even though their infectivity were similar, suggesting that K417N and E484K mutations harboring SARS-CoV-2 variant might be more transmissible than N501Y mutation containing SARS-CoV-2 variant. We also investigated the efficacy of two different monoclonal antibodies, Casirivimab and Imdevimab that neutralized SARS-CoV-2, against several kinds of pseudoviruses which indicated Wuhan or B.1.351 lineage. Remarkably, Imdevimab effectively neutralized B.1.351 lineage pseudoviruses containing N501Y, K417N, and E484K mutations, while Casirivimab partially affected them. Overall, our results underscore the importance of B.1.351 lineage SARS-CoV-2 in the viral spread and its implication for antibody efficacy.

scholarly journals The Development of Patient Scheduling Groups for an Effective Appointment System

2016 ◽  
Vol 07 (01) ◽  
pp. 43-58 ◽  
Author(s):  
Yu Li Huang
Keyword(s):  
Access To Care ◽  
Treatment Time ◽  
Optimization Technique ◽  
Urgent Care ◽  
Patient Scheduling ◽  
Total Cost ◽  
Patient Type ◽  
Clinic Efficiency ◽  
The Cost ◽  
The Impact

SummaryPatient access to care and long wait times has been identified as major problems in outpatient delivery systems. These aspects impact medical staff productivity, service quality, clinic efficiency, and health-care cost.This study proposed to redesign existing patient types into scheduling groups so that the total cost of clinic flow and scheduling flexibility was minimized. The optimal scheduling group aimed to improve clinic efficiency and accessibility.The proposed approach used the simulation optimization technique and was demonstrated in a Primary Care physician clinic. Patient type included, emergency/urgent care (ER/UC), follow-up (FU), new patient (NP), office visit (OV), physical exam (PE), and well child care (WCC). One scheduling group was designed for this physician. The approach steps were to collect physician treatment time data for each patient type, form the possible scheduling groups, simulate daily clinic flow and patient appointment requests, calculate costs of clinic flow as well as appointment flexibility, and find the scheduling group that minimized the total cost.The cost of clinic flow was minimized at the scheduling group of four, an 8.3% reduction from the group of one. The four groups were: 1. WCC, 2. OV, 3. FU and ER/UC, and 4. PE and NP. The cost of flexibility was always minimized at the group of one. The total cost was minimized at the group of two. WCC was considered separate and the others were grouped together. The total cost reduction was 1.3% from the group of one.This study provided an alternative method of redesigning patient scheduling groups to address the impact on both clinic flow and appointment accessibility. Balance between them ensured the feasibility to the recognized issues of patient service and access to care. The robustness of the proposed method on the changes of clinic conditions was also discussed.

scholarly journals The impact of boundary conditions on CO2 storage capacity estimation in aquifers

2011 ◽  
Vol 4 ◽  
pp. 4828-4834 ◽  
Author(s):  
D.J. Smith ◽  
D.J. Noy ◽  
S. Holloway ◽  
R.A. Chadwick
Keyword(s):  
Boundary Conditions ◽  
Storage Capacity ◽  
Co2 Storage ◽  
Capacity Estimation ◽  
The Impact

scholarly journals Optimal Harmonic Mitigation in Distribution Systems with Inverter Based Distributed Generation

2021 ◽  
Vol 11 (2) ◽  
pp. 774 ◽  
Author(s):  
Ahmed S. Abbas ◽  
Ragab A. El-Sehiemy ◽  
Adel Abou El-Ela ◽  
Eman Salah Ali ◽  
Karar Mahmoud ◽  
...  
Keyword(s):  
Power Quality ◽  
Distributed Generation ◽  
Distribution System ◽  
Distribution Systems ◽  
Renewable Energy Sources ◽  
Harmonic Distortion ◽  
Planning Problem ◽  
Voltage Profile ◽  
Harmonic Mitigation ◽  
The Impact

In recent years, with the widespread use of non-linear loads power electronic devices associated with the penetration of various renewable energy sources, the distribution system is highly affected by harmonic distortion caused by these sources. Moreover, the inverter-based distributed generation units (DGs) (e.g., photovoltaic (PV) and wind turbine) that are integrated into the distribution systems, are considered as significant harmonic sources of severe harmful effects on the system power quality. To solve these issues, this paper proposes a harmonic mitigation method for improving the power quality problems in distribution systems. Specifically, the proposed optimal planning of the single tuned harmonic filters (STFs) in the presence of inverter-based DGs is developed by the recent Water Cycle Algorithm (WCA). The objectives of this planning problem aim to minimize the total harmonic distortion (THD), power loss, filter investment cost, and improvement of voltage profile considering different constraints to meet the IEEE 519 standard. Further, the impact of the inverter-based DGs on the system harmonics is studied. Two cases are considered to find the effect of the DGs harmonic spectrum on the system distortion and filter planning. The proposed method is tested on the IEEE 69-bus distribution system. The effectiveness of the proposed planning model is demonstrated where significant reductions in the harmonic distortion are accomplished.

Heavy Lifters, India: Towards a Circular Economy Era

2021 ◽  
pp. 097226292110435
Author(s):  
Anupama Prashar
Keyword(s):  
Operations Management ◽  
Circular Economy ◽  
Business Models ◽  
Total Cost Of Ownership ◽  
Total Cost ◽  
Planning And Control ◽  
Cost Of Ownership ◽  
Challenges And Opportunities ◽  
And Control ◽  
The Impact

The case helps students to understand the emerging concept of linear and circular economies. It facilitates to examine the implications of circular business models such as remanufacturing on operations management decisions. It also introduces them to the concept of total cost of ownership and impact of remanufacturing on reducing total cost of ownership. The cases help students to evaluate the challenges and opportunities of remanufacturing business in emerging economy like India. This case is among the first few cases on the application of circular economy principles in context of heavy-duty and off-road sector and the impact of these principles on product design and production planning and control decisions.

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