The use of stochastic programming for optimal decison making in forest management

Optimalno gojenje in izkoriščanje gozda z namenom, da so izpolnjena vsa zahtevana načela gospodarjenja z gozdom, je predstavljeno kot večfazni stohastični proces. Kot pomoč pri optimalnem upravljanju tega procesa je prikazan stohastičen model, ki temelji na teoriji diskretnega stohastičnega programiranja. V ospredje so kot kriterij gospodarjenja z gozdom postavljeni le merljivi outputi iz gozda. Drugi učinki gozda v našem modelu niso upoštevani. Na osnovi tako definiranega kriterija gospodarjenja je optimalna strategija določena z iteracijskim postopkom, podobnim Bellmanovemu principu optimalnosti.The forest, which has to be managed with the aim to achive the prescribed silvicultural, utilization and environmental goals, is presented as a multistage stochastic process. In order to develop and manage this process, a stochastic model is described. The model is based on the theory of discrete stochastic programming. The objective is to maximize forest outputs which can be quantified. Although we are aware of many other forest benifits we did not include them in the objective function because of their intagibility. On the basis of so defined objective function, the optimal strategy is found by the use of an iterative method similar to Bellman\u27s principle of optimality

Upravljanje šumom po ekonomskom kriteriju s dinamičkim programiranjem

Šuma je vrlo sofisticirani prirodni resurs s mogućnošću neprestanog obnavljanja s kojim se treba upravljati preko određenih ekonomskih ciljeva i ciljeva iz okruženja. Proces koji usmjerava razvoj šume od početnog do konačnog stanja je dugoročan. Sastoji se od nekoliko faza i obuhvaća sekvencije relativno sličnih odluka. Zato se na politiku optimalnog upravljanja šumom može gldati kao na veliki kombinatorni problem. U modelu je problem opisan kao višefazni optimalizacijski problem u kojem se traži maksimum diskontirane vrijednosti proizvodnje drveća za vrijeme tih faza. Optimalni niz odluka koji se donosi za vrijeme rasta šume određen je korištenjem diskretne dinamičke procedure koju je razvio Bellman(1975)

Upravljanje šumom po ekonomskom kriteriju s dinamičkim programiranjem

Šuma je vrlo sofisticirani prirodni resurs s mogućnošću neprestanog obnavljanja s kojim se treba upravljati preko određenih ekonomskih ciljeva i ciljeva iz okruženja. Proces koji usmjerava razvoj šume od početnog do konačnog stanja je dugoročan. Sastoji se od nekoliko faza i obuhvaća sekvencije relativno sličnih odluka. Zato se na politiku optimalnog upravljanja šumom može gldati kao na veliki kombinatorni problem. U modelu je problem opisan kao višefazni optimalizacijski problem u kojem se traži maksimum diskontirane vrijednosti proizvodnje drveća za vrijeme tih faza. Optimalni niz odluka koji se donosi za vrijeme rasta šume određen je korištenjem diskretne dinamičke procedure koju je razvio Bellman(1975)

Editorial for the Special Issue: "Novel Solutions and Novel Approaches in Operational Research"

This special issue of Business Systems Research (SI of the BSR) is being co-published by the Slovenian Society INFORMATIKA – Section for Operational Research (SSI -SOR). It focuses on recent advances in Operations Research and Management Science (OR / MS), with a particular emphasis on linking OR / MS with other areas of quantitative and qualitative methods in the context of a multidisciplinary framework. The ten papers that were chosen for this Special Issue of the BSR present advancements and new techniques (methodology) in the field of Operations Research (OR), as well as their application in a variety of fields, including risk management, mathematical programming, game theory, gravity, spatial analysis, logistics, circular economy, continuous improvement, sustainability, e-commerce, forecasting, Gaussian processes, linear regression, multi-layer perceptron, and machine learning

Editorial for the special issue: “Novel Solutions or Novel Approaches in Operational Research”

This special issue of Business Systems Research (SI of BSR) is co-published by the Slovenian Society INFORMATIKA – Section for Operational Research (SSI – SOR) and highlights recent advances in operations research and management science (OR/MS), with a focus on linking OR/MS with other areas of quantitative and qualitative methods in a multidisciplinary framework. Nine papers that have been selected for this SI of BSR present improvements and new techniques (methodology) in operations research (OR) and their use in various fields of business, economics, spatial science and location

Editorial for the special issue: “Novel Solutions and Novel Approaches in Operational Research”

This special issue of Business Systems Research (SI of the BSR) is co-published by the Slovenian Society INFORMATIKA – Section for Operational Research (SSI -SOR) and highlights recent advances in Operations Research and Management Science (OR /MS), with a focus on linking OR /MS with other areas of quantitative and qualitative methods in a multidisciplinary framework. Eleven papers selected for this SI of the BSR present improvements and new techniques (methodology) in Operations Research (OR) and their application in various fields of economics, business, spatial science, smart mobility, higher education, human resources, environment, agriculture and social networks

Soft consensus model for the group fuzzy AHP decision making

The fuzzy analytic hierarchy process (AHP) is an extension to the classical AHP that enables dealing with the impreciseness and vagueness of judgments. It has been frequently used for handling complex decision making problems that demand a group rather than a single decision maker. Group decision making aggregates the judgments of individuals into a joint decision. Although consensus is the desired result in group decision making, it is difficult to achieve due to the diversity of opinions, knowledge and experiences of the decision makers. Therefore, the concept of soft consensus can be applied. We propose a new soft consensus based model for fuzzy AHP group decision making. The judgments in the model are presented as triangular fuzzy numbers. The closeness between judgments of two decision makers is measured by the individual fuzzy consensus index which in turn is based on the compatibility index from classical AHP. In each iteration, two decision makers with the most dissimilar opinions are identified and their judgments are adapted. The process is repeated until the desired consensus level is reached. The model can also take into account the weights of importance of individual decision makers. A fuzzy extension of the geometric mean method is employed for deriving fuzzy weights from a group fuzzy pairwise comparison matrix. The application of the model is provided in an example from the literature

Utjecaj vlasničke i posjedovne strukture na spremnost šumoposjednika na povezivanje

Private forest management is, particularly in Slovenia, far from optimal. The reason lies in the diversity of ownership and property structure. In addition, Slovenian private forest owners are not adequately organized and associated to manage their forests. The willingness of private forest owners to cooperate was evaluated using the questionnaires. The sample (n=700) included equal shares of associated and non-associated owners. Forty-six percent of questionnaires were returned. The results of the survey analysis showed that 39.1 % of private forest owners were members of forestry associations (associated), 19.9 % owners showed willingness to cooperate i.e. to join a forestry association and 41.0 % of the sampled forest owners were unwilling to cooperate. Based on the data obtained through the survey we have studied the relationship between ownership and property conditions in regard to the willingness of forest owners to cooperate. The Chi-square test showed the statistical significance of the relationship between the size of forest property and the willingness of owners to cooperate. Further, the results of multivariate logistic regression showed that it is necessary to search for private forest owners who are willing to cooperate in the group of forest owners who are younger than 50 years, who own more than 10 ha of forest land and live in common household with the co-owners.Gospodarenje privatnim šumama, posebice u Sloveniji, nije optimalno. Na to najviše utječe i raznolika vlasnička i posjedovna struktura.Šumoposjednike u gospodarenju njihovim šumama posebice ograničava mali i usitnjeni šumski posjed s velikim brojem vlasnika i suvlasnika. Zbog toga je značajno da se šumoposjednici počinju udruživati u različite organizacijske oblike povezivanja. Predviđamo da spremnost šumoposjednika za povezivanje ponajprije ovi si od neposrednih ekonomskih i socijalnih interesa šumoposjednika te od veličine i stanja njihovog šumskog posjeda. Spremnost šumoposjednika za povezivanje utvrđivali smo anketiranjem. Zbog različitih prirodnih i društvenih prilika, posjednike šuma anketirali smo u cijeloj Sloveniji. Na temelju indeksa šumoposjednika, posjednike smo podijeli u pet grupa po veličini posjeda. Unutar ovih grupa podjelili smo ih na povezane i nepovezane. Uzorak ispitanika (n=700) predstavljali su sustavno izabrani šumoposjednici. Na anketu je odgovorilo 46 % ispitanika. Uzorak je obuhvatio 322 pretežito muška šumoposjednika. Prosječna starost anketiranih vlasnika je 54 godina, s prosječno završenom osnovnom ili trogodišnjom srednjom školom. Većina anketiranih šumoposjednika živi u ruralnim sredinama. Prosječni šumski posjed iznosi 16,7 ha i nalazi se u 4,3 pros torno odvojena kompleksa. Prevladava oblik vlasništva bez suvlasništva, a šumoposjednici koji su u suvlasništvu imaju prosječno osam suvlasnika. U uzorku je 39,1 % anketiranih šumovlasnika već uključeno u različite oblike povezivanja, 19,9 % ih je spremno uključiti se u različite oblike povezivanja, dok 41 % šumoposjednika povezivanje ne interesira. Rezultati bivarijantne analize ukazuju na povezanost spremnosti za povezivanjem šumoposjednika i veličine njegovoga posjeda. Veću spremnost za povezivanje pokazuju šumoposjednici koji imaju više od 10 ha šuma. Rezultati multivarijantne analize pokazuju da se šumoposjednici koji pokazuju spremnost za povezivanje i šumoposjednici koji nisu spremni za povezivanje, razlikuju po veličini posjeda, starosti i obliku vlasništva (vlasnika je više i svi žive u istom kućanstvu). Rezultati istraživanja pokazali su da treba šumoposjednike koji su spremni za povezivanje tražiti u grupi šumoposjednika koji su stari do 50 godina, imaju šumski posjed veći od 10 ha i koji sa suvlasnicima žive u istom kućanstvu

Razvrščanje strateških in operativnih ciljev trajnostnega razvoja Pohorja, Slovenija

The combination of participatory process and multi-criteria decision methods have proven to be effective in supporting forest management decisions, since it offers inclusion of different opinions, views, and preferences of the problem. Our study is based on the results of the NATREG project, which deals with management of Pohorje, a mountain area in Slovenia. The results define six strategic goals and appertaining operative goals, which are the outcomes of workshops with different stakeholders. The aim of our study is ranking the strategic goals according to their contribution in the implementation of the "Pohorje 2030" vision and of the operative goals according to the appertaining strategic goals. Analytic hierarchy process is applied for comparisons of goals. Geometric mean method is employed for aggregating individual judgments into group judgment. The results show that all strategic goals are important, although most attention should be devoted to the goals "Preserved cultural heritage and local tradition" and "Environmental and consumer friendly usage of natural resources".Kombinacija participatornega vključevanja deležnikov v proces odločanja in večkriterijskih metod se je pri gospodarjenju z gozdom izkazala za uspešno, saj ponuja možnost vključevanja različnih mnenj, pogledov in preferenc problema. Osnova naše raziskave je projekt NATREG, ki je potekal na Pohorju v Sloveniji in v okviru katerega so določili šest strateških ciljev in pripadajoče operativne cilje. Cilj raziskave je razvrstitev strateških ciljev glede na njihov prispevek k uresničitvi vizije ŽPohorje 2030Ž in operativnih ciljev glede na pripadajoči strateški cilj. Za primerjavo ciljev smo uporabili metodo analitičnega hierarhičnega procesa. Individualne ocene smo združili v skupno oceno z geometrijsko sredino. Rezultati kažejo, da so pomembni vsi strateški cilji, najbolj pa "Ohranjena kulturna dediščina in lokalna izročila" in "Okolju in uporabniku prijazna raba naravnih virov"

Ranking strategic and operative goals for sustainable development of Pohorje, Slovenia

The combination of participatory process and multi-criteria decision methods have proven to be effective in supporting forest management decisions, since it offers inclusion of different opinions, views, and preferences of the problem. Our study is based on the results of the NATREG project, which deals with management of Pohorje, a mountain area in Slovenia. The results define six strategic goals and appertaining operative goals, which are the outcomes of workshops with different stakeholders. The aim of our study is ranking the strategic goals according to their contribution in the implementation of the “Pohorje 2030” vision and of the operative goals according to the appertaining strategic goals. Analytic hierarchy process is applied for comparisons of goals. Geometric mean method is employed for aggregating individual judgments into group judgment. The results show that all strategic goals are important, although most attention should be devoted to the goals “Preserved cultural heritage and local tradition” and “Environmental and consumer friendly usage of natural resources”