J software for forest modeling and planningPlease, contact the author Juha Lappi for additional information
J is a general program for doing different tasks in optimization, data analysis, matrix computations and simulation. It has also tools for handling splines and plotting figures. It is intended to be used mainly in different forestry related applications. It will supersede previous linear programming software JLP .
The linear optimization functions in J are designed to solve efficiently Model I type of linear programming problems, where there are several treatment schedules for management units and the goal is to select optimal schedule combinations with linear programming. For instance, we may want to maximize net present value of future incomes, subject to constraints that the income level is nondecreasing in each subregion and the total volume after planning period is above a minimum level. Constraints can be specified to domains, i.e., subsets of management units.
From version 2.0 onwards, J software is able to solve factory problems. In a factory problem, the transportations costs of different timber assortments at specified time periods and capacities of factories at the same time periods are included in the problem definition.
J is operated using text command lines, but it contains tools which make this kind of operation mode more efficient. The software is console application and it is tested to run on Windows 7 and Windows XP operating systems.
J is freely available for teaching and research. Commercial use or use in practical forest planning requires commercial license and annual license fees.
Other software made by Juha Lappi:
JLP - linear programming
JLP is an old linear programming package for solving Model I type forest management planning and conventional LP problems.
JLP is described in : Lappi, J. 1992, JLP - A linear programming package for management planning. Finnish Forest Research Institute Research papers. 414, 134 p
More information about J products.