scholarly journals A METHOD FOR SOLVING THE CANONICAL PROBLEM OF TRANSPORT LOGISTICS IN CONDITIONS OF UNCERTAINTY

2021 ◽  
pp. 80-88
Author(s):  
Lev Raskin ◽  
Yurii Parfeniuk ◽  
Larysa Sukhomlyn ◽  
Mykhailo Kravtsov ◽  
Leonid Surkov
Keyword(s):  
Nonlinear Programming ◽  
Initial Data ◽  
Computational Procedure ◽  
Complex Problem ◽  
Small Sample ◽  
Goal Development ◽  
The Cost ◽  
Transportation Plan ◽  
Cost Of Transportation ◽  
Transport Logistics

Subject.The canonical task of transport logistics in the distributed system "suppliers - consumers" is considered. Goal. Development of an accurate algorithm for solving this problem according to the probabilistic criterion in the assumption of the random nature of transportation costs has been done. Tasks. 1. Development of an exact method for solving the problem of finding a plan that minimizes the total cost of transportation in conditions when their costs are given by their distribution densities. 2. Development of a method for solving the problem when the distribution density of the cost of transportation is not known. Methods. A computational scheme for solving the problem is proposed, which is implemented by an iterative procedure for sequential improvement of the transportation plan. The convergence of this procedure is proved. In order to accelerate the convergence of the computational procedure to the exact solution, an alternative method is proposed based on the solution of a nontrivial problem of fractional nonlinear programming. The method reduces the original complex problem to solving a sequence of simpler problems. The original problem is supplemented by considering a situation that is important for practice when, in the conditions of a small sample of initial data, there is no possibility of obtaining adequate analytical descriptions for the distribution densities of the random costs of transportation. To solve the problem in this case, a minimax method is proposed for finding the best transportation plan in the most unfavorable situation, when the distribution densities of the random cost of transportation are the worst. To find such densities, the modern mathematical apparatus of continuous linear programming was used. Results. A mathematical model and a method for solving the problem of transport logistics in conditions of uncertainty of the initial data are proposed. The desired plan is achieved using the solution of the fractional nonlinear programming problem. Conclusions: The problem of forming a transportation plan is considered, provided that their costs are random values. Also, a method for solving the problem of optimization of transportation for a situation where the density of distribution of random cost cannot be correctly determined is considered.

scholarly journals DEVELOPMENT OF METHODS FOR SUPPLY MANAGEMENT IN TRANSPORTATION NETWORKS UNDER CONDITIONS OF UNCERTAINTY OF TRANSPORTATION COST VALUES

2021 ◽  
pp. 108-123
Author(s):  
Lev Raskin ◽  
Oksana Sira ◽  
Yurii Parfeniuk ◽  
Kseniia Bazilevych
Keyword(s):  
Original Problem ◽  
Transportation Cost ◽  
Exact Algorithm ◽  
Computational Procedure ◽  
Small Sample ◽  
Logistics System ◽  
The Given ◽  
Random Nature ◽  
Transportation Plan ◽  
Cost Of Transportation

The problem of transport management in a distributed logistics system "suppliers – consumers" is considered. Under the assumption of a random nature of transportation costs, an exact algorithm for solving this problem by a probabilistic criterion has been developed. This algorithm is implemented by an iterative procedure for sequential improvement of the transportation plan. The rate of convergence of a computational procedure to an exact solution depends significantly on the dimension of the problem and is unacceptably low in real problems. In this regard, an alternative method is proposed, based on reducing the original problem to solving a nontrivial problem of fractional-nonlinear programming. A method for solving this problem has been developed and substantiated. The corresponding computational algorithm reduces the fractional-nonlinear model to the quadratic one. The resulting problem is solved by known methods. Further, the original problem is supplemented by considering a situation that is important for practice, when in the conditions of a small sample of initial data there is no possibility of obtaining adequate analytical descriptions for the distribution densities of the random costs of transportation. In this case, the available volume of statistical material is sufficient only to estimate the first two moments of unknown distribution densities. For this marginal case, a minimax method for finding the transportation plan is proposed. The first step is to solve the problem of determining the worst distribution density with the given values of the first two moments. In the second step, the transportation plan is found, which is the best in this most unfavorable situation, when the distribution densities of the random cost of transportation are the worst. To find such densities, let’s use the modern mathematical apparatus of continuous linear programming

Evaluation Of The Functional Of Space-Planning Arrangement Of A Building

2019 ◽  
pp. 4-9
Keyword(s):  
Numerical Simulation ◽  
Life Cycle ◽  
Initial Data ◽  
Objective Assessment ◽  
Objective Evaluation ◽  
Point Of View ◽  
Shopping Centers ◽  
Space Planning ◽  
Planning Decisions ◽  
The Cost

The article focuses on the problem of the lack of objective evaluation of space-planning arrangement of buildings as a creative approach of the architect to the performing of functional tasks by the object. It is proposed to create a methodology for assessing the functional of space-planning solutions of buildings on the basis of numerical simulation of functional processes using the theory of human flows. There is a description of the prospects of using this method, which makes it possible to increase the coefficient of compactness, materials and works saving, more efficient use of space, reduce the cost of the life cycle of the building, save human forces and time to implement the functional of the building. The necessary initial data for modeling on the example of shopping and shopping-entertainment centers are considered. There are three main tasks for algorithmization of the functional of shopping centers. The conclusion is made about necessity of development of a method for objective assessment of buildings from the point of view of ergonomics of space-planning decisions based on the study of human behavior in buildings of different purposes.

OPTIMAL FEASIBLE SOLUTIONS TO A ROAD FREIGHT TRANSPORTATION PROBLEM

2020 ◽  
Vol 5 (1) ◽  
pp. 456
Author(s):  
Tolulope Latunde ◽  
Joseph Oluwaseun Richard ◽  
Opeyemi Odunayo Esan ◽  
Damilola Deborah Dare
Keyword(s):  
Transportation Problem ◽  
Optimal Solution ◽  
Transportation Cost ◽  
North West ◽  
Life Problems ◽  
Basic Feasible Solutions ◽  
Feasible Solutions ◽  
Road Freight Transportation ◽  
The Cost ◽  
Cost Of Transportation

For twenty decades, there is a visible ever forward advancement in the technology of mobility, vehicles and transportation system in general. However, there is no "cure-all" remedy ideal enough to solve all life problems but mathematics has proven that if the problem can be determined, it is most likely solvable. New methods and applications will keep coming to making sure that life problems will be solved faster and easier. This study is to adopt a mathematical transportation problem in the Coca-Cola company aiming to help the logistics department manager of the Asejire and Ikeja plant to decide on how to distribute demand by the customers and at the same time, minimize the cost of transportation. Here, different algorithms are used and compared to generate an optimal solution, namely; North West Corner Method (NWC), Least Cost Method (LCM) and Vogel’s Approximation Method (VAM). The transportation model type in this work is the Linear Programming as the problems are represented in tables and results are compared with the result obtained on Maple 18 software. The study shows various ways in which the initial basic feasible solutions to the problem can be obtained where the best method that saves the highest percentage of transportation cost with for this problem is the NWC. The NWC produces the optimal transportation cost which is 517,040 units.

447 Cost-Effectiveness of a 3-Year Tele-OSA Intervention

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A177-A177
Author(s):  
Jaejin An ◽  
Dennis Hwang ◽  
Jiaxiao Shi ◽  
Amy Sawyer ◽  
Aiyu Chen ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Willingness To Pay ◽  
Incremental Cost ◽  
Economic Benefits ◽  
Small Sample ◽  
Apnea Hypopnea Index ◽  
Obstructive Sleep ◽  
Group 2 ◽  
The Cost

Abstract Introduction Trial-based tele-obstructive sleep apnea (OSA) cost-effectiveness analyses have often been inconclusive due to small sample sizes and short follow-up. In this study, we report the cost-effectiveness of Tele-OSA using a larger sample from a 3-month trial that was augmented with 2.75 additional years of epidemiologic follow-up. Methods The Tele-OSA study was a 3-month randomized trial conducted in Kaiser Permanente Southern California that demonstrated improved adherence in patients receiving automated feedback messaging regarding their positive airway pressure (PAP) use when compared to usual care. At the end of the 3 months, participants in the intervention group pseudo-randomly either stopped or continued receiving messaging. This analysis included those participants who had moderate-severe OSA (Apnea Hypopnea Index >=15) and compared the cost-effectiveness of 3 groups: 1) no messaging, 2) messaging for 3 months only, and 3) messaging for 3 years. Costs were derived by multiplying medical service use from electronic medical records times costs from Federal fee schedules. Effects were average nightly hours of PAP use. We report the incremental cost per incremental hour of PAP use as well as the fraction acceptable. Results We included 256 patients with moderate-severe OSA (Group 1, n=132; Group 2, n=79; Group 3, n=45). Group 2, which received the intervention for 3 months only, had the highest costs and fewest hours of use and was dominated by the other two groups. Average 1-year costs for groups 1 and 3 were $6035 (SE, $477) and $6154 (SE, $575), respectively; average nightly hours of PAP use were 3.07 (SE, 0.23) and 4.09 (SE, 0.42). Compared to no messaging, messaging for 3 years had an incremental cost ($119, p=0.86) per incremental hour of use (1.02, p=0.03) of $117. For a willingness-to-pay (WTP) of $500 per year ($1.37/night), 3-year messaging has a 70% chance of being acceptable. Conclusion Long-term Tele-OSA messaging was more effective than no messaging for PAP use outcomes but also highly likely cost-effective with an acceptable willingness-to-pay threshold. Epidemiologic evidence suggests that this greater use will yield both clinical and additional economic benefits. Support (if any) Tele-OSA study was supported by the AASM Foundation SRA Grant #: 104-SR-13

IMPROVING THE RELIABILITY OF TRAILED DUMP VEHICLES

2021 ◽  
Vol 2 (21) ◽  
pp. 89-96
Author(s):  
E.V. Ibragimov ◽  
Keyword(s):  
Automotive Industry ◽  
Structural Strength ◽  
Operational Reliability ◽  
Technical Solution ◽  
Industrial Complex ◽  
Quality And Safety ◽  
The Russian Federation ◽  
Cargo Transportation ◽  
The Cost ◽  
Cost Of Transportation

Increasing the productivity and efficiency of agricultural cargo transportation in the agro-industrial complex of the Russian Federation is achieved through the use of tractor trains consist-ing of tractors and trailer links, the main of which are trailers. This method allows you to ensure the quality and safety of agricultural goods, as well as reduce the cost of transportation. During the analysis of the known designs of tractor-trailer dump trailers, it was revealed that a character-istic drawback is the imperfection of the design of the locking elements of the platforms designed to fix them on the chassis. As a result, a promising technical solution was developed, which, in comparison with the known ones, has a simple design and increased efficiency when fixing the bodies on the chassis. The article describes the design and the principle of operation of this tech-nical solution. The results of the structural strength calculation are presented. The conducted check showed that the obtained value of the safety factor, equal to 2.2, will ensure the operational reliability of trailed dump vehicles. The results of the study are recommended to both domestic and foreign research institutes, design and production structures of the automotive industry for further study and refinement of the proposed device with a view to its possible implementation in practice.

EXPLORING TWO COST-ADJUSTMENT METHODS FOR SELECTION BIAS IN A SMALL SAMPLE: USING A FETAL CARDIOLOGY DATASET

2014 ◽  
Vol 30 (3) ◽  
pp. 325-332 ◽  
Author(s):  
Hema Mistry
Keyword(s):  
Selection Bias ◽  
Small Sample ◽  
Economic Evaluations ◽  
Scoring Methods ◽  
Regression Analyses ◽  
Cost Estimates ◽  
Propensity Scoring ◽  
The Cost ◽  
Cost Differences ◽  
Direct Referral

Objectives: In economic evaluations of healthcare technologies, situations arise where data are not randomized and numbers are small. For this reason, obtaining reliable cost estimates of such interventions may be difficult. This study explores two approaches in obtaining cost estimates for pregnant women screened for a fetal cardiac anomaly.Methods: Two methods to reduce selection bias in health care: regression analyses and propensity scoring methods were applied to the total mean costs of pregnancy for women who received specialist cardiac advice by means of two referral modes: telemedicine and direct referral.Results: The observed total mean costs of pregnancy were higher for the telemedicine group than the direct referral group (4,918 versus 4,311 GBP). The regression model found that referral mode was not a significant predictor of costs and the cost difference between the two groups was reduced from 607 to 94 GBP. After applying the various propensity score methods, the groups were balanced in terms of sizes and compositions; and again the cost differences between the two groups were smaller ranging from -62 (matching “by hand”) to 333 GBP (kernel matching).Conclusions: Regression analyses and propensity scoring methods applied to the dataset may have increased the homogeneity and reduced the variance in the adjusted costs; that is, these methods have allowed the observed selection bias to be reduced. I believe that propensity scoring methods worked better for this dataset, because after matching the two groups were similar in terms of background characteristics and the adjusted cost differences were smaller.

Computerized Selection of Optimum Machining Conditions for a Job Requiring Multiple Operations

1978 ◽  
Vol 100 (3) ◽  
pp. 356-362 ◽  
Author(s):  
S. S. Rao ◽  
S. K. Hati
Keyword(s):  
Nonlinear Programming ◽  
Mathematical Programming ◽  
Machine Tools ◽  
Machining Conditions ◽  
Coupling Constraints ◽  
Programming Techniques ◽  
Mathematical Programming Problems ◽  
The Individual ◽  
The Cost ◽  
Selection Of

The problem of determining the optimum machining conditions for a job requiring multiple operations has been investigated. Three objectives, namely, the minimization of the cost of production per piece, the maximization of the production rate and, the maximization of the profit are considered in this work. In addition to the usual constraints that arise from the individual machine tools, some coupling constraints have been included in the formulation. The problems are formulated as standard mathematical programming problems, and nonlinear programming techniques are used to solve the problems.

scholarly journals Illicit Trade in Russian Gold and Silver Coins in West China in 1850's (based on the Materials of the Russian Consul K. A. Skachkov)

2020 ◽  
Vol 22 (1) ◽  
pp. 88-97
Author(s):  
I. R. Hamzin
Keyword(s):  
Historical Analysis ◽  
West China ◽  
Illicit Trade ◽  
Russian State ◽  
Trading Activities ◽  
The Government ◽  
Chinese Trade ◽  
State Library ◽  
The Cost ◽  
Cost Of Transportation

The present research featured the illicit trade in Russian gold and silver coins in Xinjiang in the 1850's. The paper focuses on the problems of control and customs services, as well as on the difficulties connected with the trade in Russian goods. The historical analysis was based on the documents written by Konstantin Adrianovich Skachkov, the then Russian Consul in Chuguchak. The materials were obtained from the Research Department of Manuscripts of the Russian State Library. In his report, Consul K. A. Skachkov compared the state of the markets of the Russian-Chinese trade in Chuguchak and Kyakhta. He highlighted the broad prospects for trade development in Xinjiang. The Consul paid great attention to the problems on the young market of Central Asia and proposed some measures to improve the situation. He performed a comparative analysis of the trading activities of a Russian merchant and a smuggler. The analysis makes it possible to reconstruct the trading process, determine the cost of transportation, and formulate the commercial benefit resulting from the legal trade and the contraband trade. K. A. Skachkov concluded that despite the high potential for trade development, the region was torn apart by substantial internal contradictions and demanded greater attention from the government. The illicit trade in Russian coins was caused by the barter trading on the Xinjiang market in 1850's.

scholarly journals ESTIMATED TRANSPORTATION COST OF LOW-TONNAGE LNG

2020 ◽  
Vol 17 (5) ◽  
pp. 130-163
Author(s):  
O. V. Tarovik ◽  
O. M. Mudrova
Keyword(s):  
Coastal Waters ◽  
Unit Cost ◽  
Transportation Cost ◽  
Model Calculations ◽  
Inland Waterways ◽  
Universal Approach ◽  
Environmental Requirements ◽  
Regression Relations ◽  
The Cost ◽  
Cost Of Transportation

Demand for low-tonnage transportation of LNG requires improved logistics. Assessing the value of all parts of the supply chain is an important component of solving the problem of optimizing transportation costs for both consumers and LNG suppliers. In connection with tightening of environmental requirements regarding bunker fuel, the task of optimizing the supply of LNG for water transport by the cost of transportation becomes particularly relevant.The objective of the study is to develop a universal approach to estimating the cost of transporting low-tonnage LNG for bunkering vessels in the Russian Federation.The research methodology is focused on the analytical method based on a system-structural approach.As part of the departmental project of the Russian Ministry of Industry and Trade «Development of  gaspowered fleet for navigation in coastal waters and inland waterways», the authors developed technical and economic models for calculating the unit cost of LNG transportation by road and water. To calculate the unit cost of LNG transportation by rail, the data of TMkarta information and reference system were used. Based on model calculations and data of TMkarta system, regression relations were obtained that allow one to determine the cost of transportation for various options of transport and technological schemes based on a limited set of parameters. An approach has also been proposed for estimating the cost of LNG transshipment. The regression ratios were tested for selected routes. As a result,conclusions were drawn about the most effective LNG transportation options.

scholarly journals Clustering Control of Multi-Objective Problems with Application to E-commerce

2018 ◽  
Vol 1 (1) ◽  
pp. 41
Author(s):  
Liang Chen ◽  
Xingwei Wang ◽  
Jinwen Shi
Keyword(s):  
Ant Colony Algorithm ◽  
Time Window ◽  
Ant Colony ◽  
Distribution Area ◽  
Routing Problem ◽  
Logistics Distribution ◽  
Multi Objective ◽  
The Cost ◽  
Vehicle Capacity ◽  
Cost Of Transportation

In the existing logistics distribution methods, the demand of customers is not considered. The goal of these methods is to maximize the vehicle capacity, which leads to the total distance of vehicles to be too long, the need for large numbers of vehicles and high transportation costs. To address these problems, a method of multi-objective clustering of logistics distribution route based on hybrid ant colony algorithm is proposed in this paper. Before choosing the distribution route, the customers are assigned to the unknown types according to a lot of customers attributes so as to reduce the scale of the solution. The discrete point location model is applied to logistics distribution area to reduce the cost of transportation. A mathematical model of multi-objective logistics distribution routing problem is built with consideration of constraints of the capacity, transportation distance, and time window, and a hybrid ant colony algorithm is used to solve the problem. Experimental results show that, the optimized route is more desirable, which can save the cost of transportation, reduce the time loss in the process of circulation, and effectively improve the quality of logistics distribution service.

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