scholarly journals Harvest scheduling with spatial aggregation for two and three strip cut system under shelterwood management

2011 ◽  
Vol 57 (No. 6) ◽  
pp. 271-277 ◽  
Author(s):  
M. Konoshima ◽  
R. Marušák ◽  
A. Yoshimoto
Keyword(s):  
Spatial Aggregation ◽  
Decision Variable ◽  
Scheduling Problem ◽  
Harvest Scheduling ◽  
Aggregation Method ◽  
Management Units ◽  
Decision Variables ◽  
Optimal Harvest ◽  
Cutting System ◽  
Sequential Cuts

We propose a spatial aggregation method to solve an optimal harvest scheduling problem for strip shelterwood management. Strip shelterwood management involves either a two-cut system with a preparatory-removal cut cycle, or a three-cut system with a preparatory-establishment-removal cut cycle. In this study we consider these connected sequential cuts as one decision variable, then employ conventional adjacency constraints to seek the best combination of sequential cuts over space and time. Conventional adjacency constraints exclude any spatially-overlapped strips in the decision variables. Our results show the proposed approach can be used to analyze a strip shelterwood cutting system that requires "connectivity" of management units.

Optimal harvest scheduling at the forest level in the presence of the risk of fire

1986 ◽  
Vol 16 (2) ◽  
pp. 266-278 ◽  
Author(s):  
W. J. Reed ◽  
D. Errico
Keyword(s):  
Dynamic Equations ◽  
Scheduling Problem ◽  
Deterministic Approach ◽  
Harvest Scheduling ◽  
Forest Harvest ◽  
Timber Supply ◽  
Reasonable Approximation ◽  
Optimal Harvest ◽  
The Impact ◽  
Scheduling Models

The effect of fire on forest yields has been well documented in stand-level analyses; however, forest-level effects are less widely known. A set of dynamic equations can be constructed that describe the evolution of a forest under the impact of harvesting and random fire. When fire is treated in a deterministic fashion, these equations can be used to formulate an optimal harvest scheduling problem that can be solved using linear programming. Examples using white spruce data for the Fort Nelson Timber Supply Area of British Columbia show that even modest rates of fire can have a dramatic impact and that present harvest scheduling models may be considerably overestimating projected forest harvest levels. Results also show that the deterministic approach appears to be a reasonable approximation of the true stochastic fire problem.

Influence of land classification systems on timber harvest scheduling models

1990 ◽  
Vol 20 (2) ◽  
pp. 172-178 ◽  
Author(s):  
M. S. Jamnick ◽  
L. S. Davis ◽  
J. K. Gilless
Keyword(s):  
Objective Function ◽  
Timber Harvest ◽  
Management Unit ◽  
Harvest Scheduling ◽  
Land Classification ◽  
Decision Variables ◽  
Optimal Harvest ◽  
Stand Type ◽  
Objective Function Values ◽  
Scheduling Models

Differences between linear program based timber harvest schedules that use decision variables based on stand types (homogeneous but generally noncontiguous areas) and management units (generally heterogeneous but contiguous areas) were investigated. It was proposed that (i) optimal harvest schedules identified using stand type decision variables should have larger present net value objective function values than those identified using models with management unit decision variables, (ii) optimal present net value objective function values in management unit models should decline as management unit size is increased, and (iii) as the number of management choices increases, differences between stand type and management unit optimal present net values should decrease. The propositions were tested using 48 linear programming timber harvest scheduling models constructed for the University of California's Blodgett Forest Experiment Station. These models, which form 12 model groups, differ in the numbers and type of prescriptions considered for existing or regenerated stands, and harvest flow or ending inventory policies. The results generally supported the propositions and indicate that the number of management choices considered in the timber harvest scheduling model is probably a more important factor influencing the optimal harvest schedules than is land classification.

Optimal harvest scheduling in Eucalyptus plantations

2009 ◽  
Vol 11 (8) ◽  
pp. 548-554 ◽  
Author(s):  
Luis Diaz-Balteiro ◽  
Mercedes Bertomeu ◽  
Manuel Bertomeu
Keyword(s):  
Harvest Scheduling ◽  
Optimal Harvest ◽  
Eucalyptus Plantations

scholarly journals Religiosity in The Decision to Use Islamic Banking Products

2020 ◽  
Vol 4 (2) ◽  
pp. 196-225
Author(s):  
Indra Kurniawan
Keyword(s):  
Significant Influence ◽  
Joint Effect ◽  
Islamic Banking ◽  
Decision Variable ◽  
Decision Variables

This study aims to examine the effect of religiosity on decisions to use Islamic banking products; whether there is an influence between the facilities on the decision to use Islamic banking products; whether there is an influence between knowledge on the decision to use Islamic banking products; and whether there is an influence between promotion on the decision to use Islamic banking products. Based on the results of research and discussion, it can be concluded. First, religiosity does not have a significant effect on the variables of customer decisions in using banking products. Second, the facility has a significant influence on the customer's decision variable in using Islamic banking products. Third, knowledge has a significant influence on customer decision variables in using Islamic banking products. Fourth, the promotion has a significant influence on customer decision variables in using Islamic banking products. Fifth, religiosity does not affect, while facilities, knowledge, and promotions have a joint effect on customer decisions in using sharia banking products at BNI Syariah.

scholarly journals OPTIMIZATION OF B-SERIES PROPELLER DESIGN AS KCR 60 PROPULSOR TO ACHIEVE OPTIMAL PERFORMANCE USING MATHEMATICAL MODEL

JOURNAL ASRO ◽  
2019 ◽  
Vol 10 (3) ◽  
pp. 83
Author(s):  
Akhmat Nuryadin ◽  
Abdul Rahman ◽  
Cahyanto Cahyanto
Keyword(s):  
Objective Function ◽  
Area Ratio ◽  
Diameter Ratio ◽  
Decision Variable ◽  
Propeller Design ◽  
A Value ◽  
Decision Variables ◽  
Blade Area ◽  
Calculation Results ◽  
Constraint Variable

The process of designing a propeller as a ship propulsor is an important step to produce a propeller that has the ability to achieve the desired target speed of the ship. Propeller optimization is an effort to produce a propeller design with optimal capabilities. This propeller design uses a B-series propeller where this propeller is commonly used as ship propulsor. Optimization steps to find the optimal propeller, namely: determining the objective function, determining the decision variable, and determining the constraint variable. The objective function of this optimization is to determine the Advanced-optimal (J-opt) coefficient value for the propeller. The J-opt coefficient must have a value greater than the J-Design coefficient (J-d) value and the smallest possible value (minimization function). For decision variables include picth diameter ratio (P / D) and Blade area ratio (Ae / Ao) and number of leaves (Z). While the constraint variables are: the pitch diameter ratio value of the B-series propeller (0.5≤P/D≤1.4), the blade area ratio B-series (0.3≤Ae/Ao≤1, 05) as well as the number of blade (2≤Z≤7). From the calculation results of the optimization of the B-series propeller design for the KCR 60, the optimum value is different for each blade. the propeller with the number of blade 2 (Z = 2) obtained the optimum propeller with the value of J-opt =0.77098733, Ae/Ao=0.3, P/D=1.13162337, KT = 0.165632781, 10KQ=0, 27546033 and efficiency=0.73198988. Popeller with number of blades 3 (Z=3) obtained optimum propeller with J-opt value=0.77755594, Ae/Ao=0.3, P/D=1.06370107, KT=0.168069763, 10KQ=0.28984068 and efficiency=0.70590799. Propeller with number of blades 4 (Z=4) obtained optimum propeller with J-opt value=0.78478688, Ae/Ao=0.45954773, P/D=1.03798312, Kt=0.172147709, 10Kq= 0.3091063 and efficiency=0.67797119. Propeller with blades number 5(Z=5) obtained optimum propeller with J-opt value=0.78575616, Ae/Ao=0.65607164, P/D=1.02716571, KT=0.174099168, 10KQ=0.31376705 and efficiency=0.67547177. Propeller with blades number 6 (z=6) obtained optimum propeller with J-opt value=0.78867357, Ae/Ao=0.71124343, P/D=1.0185055, KT=0.176525247, 10KQ=0.32215257 and efficiency =0.66705719. Propeller with number of blades 7 (Z=7) obtained optimum propeller with J-opt value=0.7949898, Ae/Ao=0.69772623, P/D=1.01780081, KT=0.181054792, KQ=0.34011349 , and efficiency =0.64804328.Keywords : KCR, Optimization,Wageningen B-series.

Qualitative simulation of organization quality specific immune decision-making of manufacturing enterprises based on QSIM algorithm simulation

2021 ◽  
pp. 1-18
Author(s):  
Qiang Liu ◽  
Xiaoli Qu ◽  
Danyu Zhao ◽  
Yu Guo
Keyword(s):  
Decision Making ◽  
Simulation Method ◽  
Engineering Management ◽  
Decision Variable ◽  
Science And Engineering ◽  
Qualitative Simulation ◽  
Manufacturing Enterprises ◽  
Decision Variables ◽  
Organization Quality ◽  
Simulation Results

Quality is the core of the enterprise, strengthening organization quality specific immune is the key channel. Organization quality specific immune belongs to science and engineering management field, QSIM qualitative simulation method that refer to computational simulation algorithm is widely used in the science and engineering management field, QSIM qualitative simulation method can solve science and engineering management issues effectively. In this study, qualitative simulation QSIM theory is used to analyze and reason the organization quality specific immune decision of manufacturing enterprises. Combined with the pressure-state-response framework, the management mechanism of organization quality specific immune is analyzed according to state variables, decision variables, system variables and environment variables, and further the qualitative simulation rules for organization quality specific immune decision-making are set according to the causal relationships among variables of organization quality specific immune. This study sets organization quality monitor, organization quality defense and organization quality memory as the decision variables, uses QSIM algorithm for simulating organization quality specific immune decision-making reasoning, compares with the influences of single decision variable and multi-decision variables on organization quality specific immune system through simulation results. Simulation results indicate that QSIM algorithm simulation can be used to simulate and reason organization quality specific immune decision-making in order to help manufacturing enterprises reasonably enhance organization quality specific immune performance and quality performance through three decision variables of organization quality monitor, organization quality defense and organization quality memory. The simulation results will provide new revelation for organization quality specific immune decision-making of manufacturing enterprises.

Preemptive scheduling with transportation delays between machines

2020 ◽  
Vol 15 (3) ◽  
pp. 829-847
Author(s):  
Ryma Zineb Badaoui ◽  
Mourad Boudhar ◽  
Mohammed Dahane
Keyword(s):  
Linear Programming ◽  
Neighborhood Search ◽  
Preemptive Scheduling ◽  
Scheduling Problem ◽  
Programming Formulation ◽  
Content Type ◽  
Decision Variables ◽  
Linear Programming Formulation ◽  
Local Search Strategy ◽  
Two Stages

Purpose This paper studies the preemptive scheduling problem of independent jobs on identical machines. The purpose of this paper is to minimize the makespan under the imposed constraints, namely, the ones that relate the transportation delays which are required to transport a preempted job from one machine to another. This study considers the case when the transportation delays are variable. Design/methodology/approach The contribution is twofold. First, this study proposes a new linear programming formulation in real and binary decision variables. Then, this study proposes and implements a solution strategy, which consists of two stages. The goal of the first stage is to obtain the best machines order using a local search strategy. For the second stage, the objective is to determine the best possible sequence of jobs. To solve the preemptive scheduling problem with transportation delays, this study proposes a heuristic and two metaheuristics (simulated annealing and variable neighborhood search), each with two modes of evaluation. Findings Computational experiments are presented and discussed on randomly generated instances. Practical implications The study has implications in various industrial environments when the preemption of jobs is allowed. Originality/value This study proposes a new linear programming formulation for the problem with variable transportation delays as well as a corresponding heuristic and metaheuristics.

scholarly journals Routing for Hazardous Materials Transportation in Urban Areas

Symmetry ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1091 ◽  
Author(s):  
Zhang ◽  
Feng ◽  
Yang ◽  
Ding
Keyword(s):  
Urban Areas ◽  
Optimal Solution ◽  
Hazardous Materials ◽  
Work Load ◽  
Decision Variable ◽  
Daily Production ◽  
Hazardous Materials Transportation ◽  
Decision Variables ◽  
Hazmat Transportation ◽  
Local Risk

Hazardous materials (HAZMAT) are important for daily production in cities, which usually have a high population. To avoid the threat to public safety and security, the routes for HAZMAT transportation should be planned legitimately by mitigating the maximum risk to population centers. For the objective of min-max local risk in urban areas, this study has newly proposed an optimization model where the service of a link for HAZMAT transportation was taken as the key decision variable. Correspondingly, the symmetric problem of min-max optimization takes significant meanings. Moreover, in consideration of the work load of solving the model under a lot of decision variables, a heuristic algorithm was developed to obtain an optimal solution. Thereafter, a case study was made to test the proposed model and algorithm, and the results were compared with those generated by deterministic solving approaches. In addition, this research is able to be an effective reference for authorities on the management of HAZMAT transportation in urban areas.

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