U radu je dodatno istražena i evaluirana točnost fotogrametrijske procjene volumena na razini sastojine. Konkretno, na području šuma hrasta lužnjaka Pokupskog bazena (g.j. Jastrebarski lugovi) ...testirana je mogućnost korištenja fotogrametrijske metode bazirane na postojećim i lako dostupnim podacima (aerosnimke, digitalni model reljefa, podaci osnove gospodarenja) kao i postojećih fotogrametrijskih modela procjene sastojinskog volumena izrađenih za šume hrasta lužnjaka Spačvanskog bazena. Iz aerosnimaka i digitalnog modela reljefa izrađen je digitalni model visine krošanja (DMVK) prostorne rezolucije 5 m. Iz DMVK-a su dobiveni metrički podaci, koji su potom korišteni kao nezavisne varijable u modelima procjene volumena sastojine. Uspoređena je točnost procjene izvornih modela izrađenih za područje Spačvanskog bazena (SB modeli) te istih modela, ali s naknadno procijenjenim lokalnim parametrima za područje Pokupskog bazena (PB modeli). Fotogrametrijski procijenjeni volumeni validirani su s volumenom sastojina iz osnove gospodarenja. Dobiveni rezultati ukazuju na značajno poboljšanje točnosti fotogrametrijske procjene volumena kod PB modela u odnosu na SB modele. Korištenjem izvornih SB modela, volumen sastojine procijenjen je s korijenom srednje kvadratne pogreške od 18,47%, dok je korištenjem dodatno parametriziranih PB modela volumen procijenjen s pogreškom od 12,03%. U ovom radu prikazana fotogrametrijska metoda procjene volumena sastojina ne može zamijeniti klasične terenske metode za potrebe uređajne inventure šuma, međutim, budući da ne zahtijeva dodatna terenska mjerenja, već se u potpunosti bazira na postojećim podacima (aerosnimke, DMR, podaci osnove gospodarenja), a uz to pruža i zadovoljavajuću točnost, može poslužiti kao učinkovita i financijski isplativa metoda u slučajevima kada je u vrlo kratkom vremenu potrebno provesti inventuru nekog većeg šumskog područja.
The application of digital aerial photogrammetry in forest inventory has been in the focus of a number of studies during the last decade (White et al. 2016, Goodbody et al. 2019). The results were tested and evaluated mostly on plot-level, and less often on stand-level (Bohlin et al. 2012, Rahlf et al. 2014, Gobakken et al. 2015, Pitt et al. 2015, Stepper et al. 2015, Puliti et al. 2016, Balenović et al. 2017, Iqbal et al. 2019). In almost all studies, a classic Area-Based Approach (ABA) which includes modelling at plot-level and ‘wall-to-wall’ mapping to estimate forest variables at stand-level were applied. A somewhat different ABA approach which implies direct modelling and estimation at stand-level were proposed by Balenović et al. (2017). This new approach, hereinafter referred to as Stand-Based Approach (SBA), is based on existing and easily available photogrammetric materials and data (aerial images from regular national topographic surveys, official national digital terrain data) as well as on data from existing forest management plans. The main precondition for the SBA method application is the approximate time coincidence between the time of aerial images acquisition and the time of the field data collection for the forest management plan generation. Similar to classical ABA, SBA also requires models (equations) for forest variable estimations. However, in SBA case, models are developed on the certain number of stands (subcompartments) of similar structural characteristics (e.g. forest management classes). In SBA, independent variables are metric stand-level data obtained from aerial images and its product (normalized point clouds or canopy height models), while reference (modelling or validation) data are obtained from regular forest management plans. Compared to classical ABA, SBA does not require additional field measurements, and therefore presents a fast and cost-effective alternative to ABA. An additional assumption is that models developed for the certain area can be applied for other forest areas with similar forest characteristics.
This work presents the continuation of previous study (Balenović i dr. 2017) with the aim to additionally test the effectiveness and accuracy of SBA method. More precisely, SBA method and existing models of stand volume estimation originally developed for lowland pedunculate oak (
Quercus robur
L.) of Spačva basin forest complex (Eastern Croatia) were tested in pedunculated oak forest of Pokupsko basin forest complex (Central Croatia).
A total of 87 even-aged pedunculate oak forest stands of Jastrebarski lugovi management unit were included in this study (Figure 1, Table 1). Photogrammetric data (aerial images, digital terrain data) were provided by the Croatian State Geodetic Administration, and were used to generate Digital Surface Model (DSM) and Digital Terrain Model (DTM). A raster Canopy Height Model (CHM) of 5 m resolution was generated by subtracting DTM from DSM (Figure 2). Metrics extracted from CHM for each stand and used for stand-level volume estimation are presented in Table 2. Equations (1) and (2) present photogrammetric models for stand-level volume estimation. A more detailed description of the models can be found in Table 3. SB-1 and SB-2 models consist of independent variables and parameters (regression constant and coefficients) originally developed for the Spačva basin area (Table 4). PB-1 and PB-2 models consisted of the same variables as SB-1 and SB-2 models, but their parameters were developed for the present study area (Pokupsko basin) (Table 4). All models were validated using the reference stand volume from the forest management plan. SB-1 and SB-2 models were validated using the entire dataset (87 stands), whereas PB-1 and PB-2 models were validated using the randomly selected 29 stands (other 58 stands were used for parameters estimation).
According to validation results (Table 2, Figure 3), PB models showed considerably greater performance than SB-models. Compared to SB-1 model, PB-1 model achieved 11% higher R2adj values, for 3,92% MD% values (absolute), and for 6,44% higher RMSE% values. Also, the results showed that the inclusion of stand age (SA) as an additional predictor in SB-2 and PB-2 models did not contribute
significantly on model performance. All models showed a similar trend (Figure 3), i.e. volume in stands with lover volume values were overestimated, while in stands with higher volume values were underestimated. However, overestimations ( 8,5%) using SB models were considerably greater than underestimations ( -4%) using PB models. Differences in SB and PB models performance are probably due to differences in stand and site characteristics between two forest areas (Spačva basin and Pokupsko basin). The obtained results suggest that the model with independent variables (Equation 1) originally developed for Spačva basin area can be used for Pokupsko basin and other areas with similar forest characteristics, but local model parameters have to be estimated in order to increase estimation accuracy. It has to be emphasized that the photogrammetric method tested in this paper can not replace the conventional field methods in regular forest inventory. However, its application is based on existing and easily available data (aerial images from regular topographic surveys, official DTM, forest management plan) and does not require additional field measurements and therefore present effective and low-cost solution when in a very short period large areas have to be inventoried. Further research should be focused on other important forest variables (e.g. mean stand height, mean stand diameter, basal area, stand density, biomass, etc.) and different forest types.
U radu je istražena mogućnost primjene digitalnih aerosnimaka visokih prostornih rezolucija za procjenu glavnih strukturnih elemenata sastojina (srednji sastojinski promjer i visina, broj stabala, ...temeljnica i volumen). Za dio gospodarske jedinice ‘Donja Kupčina – Pisarovina’ (14 odsjeka) na sistematskom uzorku ploha provedena je manualna (klasična/analogna) stereo fotogrametrijska izmjera na aerosnimkama GSD 30 cm i 10 cm (GSD – eng.
Ground Sample Distance
). Svakom stablu na plohi određena (interpretirana) je vrsta drveća, izmjerena visina i delineirana krošnja, na temelju čega su procijenjeni glavni strukturni elementi sastojina. Kako bi se utvrdila točnost fotogrametrijski procijenjenih strukturnih elemenata sastojina provedena je usporedba s podacima terenske izmjere. Rezultati provedenog istraživanja potvrdili su velik potencijal primjene digitalnih aerosnimaka visokih prostornih rezolucija u stereomodelu pri inventuri šuma. Usporedbom rezultata fotogrametrijske izmjere na digitalnim aerosnimkama GSD 30 cm i GSD 10 cm s rezultatima terenske izmjere utvrđeno je da aerosnimke GSD 30 cm pružaju mogućnost procjene srednjih sastojinskih visina, sastojinske temeljnice i volumena s gotovo jednakom točnošću kao i aerosnimke GSD 10 cm. Međutim, pogreške procijene srednjeg sastojinskog promjera i broja stabala bile su gotovo dvostruko veće na aerosnimkama GSD 30 cm nego na aerosnimkama GSD 10 cm. Stoga se može zaključiti kako aerosnimke GSD 10 cm sveukupno daju bolje rezultate procjene strukturnih elemenata sastojina, jer prikazuje strukturu sastojine bliže stvarnoj.
Although the application of aerial stereo photogrammetry in forest inventory has a long tradition, in many countries including Croatia forest inventories are based on labour and time consuming field surveys. Therefore, the objective of this research was to evaluate the applicability of using the digital aerial images of high spatial resolution (ground sampling distance – GSD of 10 cm and 30 cm) for predicting forest stand attributes (basal-area weighted mean dbh – DBHg, Lorey’s mean height – HL, stand density – N, basal area – G, volume – V). This research continues the work of the previous research (Balenović et al. 2013, 2015a), where accuracy of photogrammetrically estimated arithmetic mean diameter and arithmetic mean height of forest stands were evaluated.
The research was conducted in the even-aged (sessile oak management class) and the multi-aged stands (European beech and common hornbeam management classes) of a privately owned forest in the management unit Donja Kupčina – Pisarovina, 25 km south of Zagreb, Croatia (Figure 1). Field data were collected during the spring and summer of 2009 as part of the regular forest inventory conducted according to the valid Regulation on Forest Management. A total of 183 circular plots with radii of 8 or 12 m were systematically set in
the 14 selected subcompartments. The positions of the sample plot centres were recorded with GPS receiver. Within each plot, the diameter at breast height (dbh) was measured and tree species was determined for all trees with dbh≥10 cm. The height of each tree was calculated by means of the constructed local height curves fitted with Michailloff’s function. The basal area (g) of each tree was calculated from the measured dbhs using standard equation, whereas the merchantable tree volume up to a diameter of 7 cm overbark (v) was calculated from field-measured dbh and estimated h using the Schumacher-Hall function and parameters from Croatian volume tables. The forest stand attributes were calculated by averaging data of all sampled tree within each stand (DBHg, HL) or summing the tree data and dividing it by the total area of all plots for each stand (N, G, V). Stand-level field data were used in the statistical analysis and comparison with photogrammetric data as a ground-truth reference data (Table 1).
The colour infrared (CIR) digital aerial images of GSD 30 cm and GSD 10 cm were acquired using a Microsoft UltraCamX digital large-format aerial camera during two aerial surveys in July 2009 (Figure 1, Table 2). The digital terrain data (breaklines, formlines, spot heights and mass points) for the digital terrain model (DTM) generation were collected by stereo-mapping of digital aerial images according to the rules of the Croatian State Geodetic Administration. The whole procedure of image acquisition, aerial triangulation, and collection of 3D data was conducted by Geofoto Ltd. (Zagreb, Croatia).
The photogrammetric stereo measurements and the visual interpretation of tree attributes were performed on digital aerial images of 30 cm GSD and 10 cm GSD using PHOTOMOD 5.24 digital photogrammetric system according to procedures described in Balenović et al. 2013, 2015a. The photogrammetric plots were overlaid upon the aerial images based on the spatial coordinates (x, y) of the field plot centres recorded by the GPS receiver. The determination of tree species and crown tops as well as the delineation of crown areas was performed manually for each tree whose top fell inside the plot. The height of each tree was calculated as the difference between the tree top elevations and the corresponding tree bottom elevations determined from the DTM. A raster DTM of 1 m grid size was generated through linear interpolation of a triangular irregular network (TIN) which was previously created from the digital terrain data. The dbh of each tree on the plot was calculated using local regression models with tree height and crown diameter as inputs (Balenović et al. 2012). Crown diameter was calculated from delineated crown area by applying the equation for circle surface area. Further calculations of photogrammetric tree (g, v) and stand variables (DBHg, HL, N, G, V) were identical to previously described calculations of field data.
The accuracy of the photogrammetrically estimated stand attributes was evaluated by calculating differences (D), mean differences (MD) and RMSE between photogrammetric- and field-estimates. The relative values of D%, MD%, RMSE% were calculated according to the mean of the field reference values. The D and D% were calculated for each subcompartment, whereas MD, MD%, RMSE and RMSE% were calculated for the whole study area.
The results in Table 3 show that photogrammetric measurements of the aerial images of 30 cm GSD (PM30) and 10 cm GSD (PM10) produced reasonable accurate estimates for HL, G, V with relative RMSEs ranging from 3.65% to 5.36%. Similar accuracy was obtained for DBHg estimated by PM10 (RMSE=4.94%), while lower accuracy was obtained for N estimated by PM10 (RMSE=7.71%) and DBHg estimated by PM30 (RMSE=9.460%). The lowest accuracy was obtained for N estimated by PM30 (RMSE=15.90%). Both photogrammetric measurements (PM10 and PM30) estimated HL and G with similar level of accuracy, whereas V was estimated with slightly higher accuracy by PM10 then by PM30. For estimation of DBHg and V, PM10 produced considerably better results, i.e. estimates of approximately twice higher accuracy then PM30. Figure 2 shows relations between D% and field estimates of corresponding attributes for each subcompartment. As can be seen, photogrammetrically estimated HL and V varied between overestimation and underestimation (HL: from -13.6% to 2.8% for PM10, from -12.8% to 3.7% for PM30; V: from -7.0% to 2.2% for PM10, from -10.2% to 8.2% for PM30), but with a slight tendency to underestimate field estimates. Photogrammetrically estimated G also varied between overestimation and underestimation (from -6.2% to 12.9% for PM10, from -5.0% to 10.2% for PM30), but with a slight tendency to overestimate field estimates. DBHg was overestimated for all subcompartments by both photogrammetric measurements (from 1.1 to 9.5% for PM10; from 3.0% to 16.5% for PM30). On the contrary, both photogrammetric measurements underestimated N throughout all subcompartments (from -2.6% to -10.6% for PM10; from -5.1% to -24.4% for PM30). For both DBHg and N, PM30 produced estimates of lower accuracy than PM10. This is a consequence of lesser visibility of details (e.g. crown boundaries) on images of lower spatial resolution (GSD 30 cm) and decreased ability to detect individual trees, especially in the part of stands with greater proportion of younger trees. According to Figure 3, the notable underestimation of N by PM30 was found in the lowest dbh size class (10.0-14.9 cm).
The results of this research showed that HL, G and V can be accurately estimated by manual measurements of digital aerial images of high spatial resolution. The use of images of high spatial resolution, along with the
use of local dbh models, led to improved accuracy regarding individual tree detection and dbh estimation. Moreover, the errors of N underestimation and DBH overestimation have been mutually abolished, which in the end resulted with reasonably accurate estimates of G and V at stand level. Since the errors of N underestimation and DBH overestimation with PM30 were both proportionally (twice) greater than with PM10, G and V were estimated on both 10 cm and 30 cm GSD images with similar level of accuracy. Although PM10 overall produced the more accurate results than PM30, it should be noted that the price of 10 cm images is several time higher than of 30 cm images. Therefore, a potential user should decide which images to use depending on desired accuracy and available funds.
Urbane su šume vrijedan prirodni resurs koji pruža višestruke koristi (ekološke, ekonomske i
dru štvene) i svojevrsna su »priroda na kućnom pragu« za gradsko stanovništvo. Više od polovice
svjetskoga ...stanovništva živi u urbanim sredinama, što zasigurno utječe na kakvoću života
gra đana. Stoga koncept urbanoga šumarstva stavlja naglasak na društvene aspekte, kao što su
pru žanje mjesta za odmor i rekreaciju, utjecaj na zdravstveno stanje ljudi te edukativna uloga
urbanih šuma za građane. Šumarska istraživanja u Hrvatskoj o urbanim šumama uglavnom ne
uključuju društvene aspekte. Živimo u svijetu u kojem tehnologija igra važnu ulogu. Mobiteli,
»pametni« telefoni ili navigacija u automobilima dio su svakodnevnice, a zajedničko im je da se
svi koriste globalnim pozicijskim sustavom (GPS), koji se primjenjuje za određivanje položaja
objekta u prostoru. U ovom se radu prikazuju mogućnosti primjene GPS-a u istraživanjima
društvenih aspekata urbanoga šumarstva s obzirom na rekreaciju, zdravlje ljudi, ali i informiranje
i edukaciju građana o urbanim šumama. Za te su potrebe korištene baze SCOPUS, Science
Direct i Google Scholar. Navedeni primjeri pokazuju velike mogućnosti primjene GPS-a, osobito
u kombinaciji s geografskim informacijskim sustavom (GIS) za istraživanje društvenih
aspekata urbanoga šumarstva.
Za potrebe pojednostavljenja poslova upravljanja robom, razvili smo novo rješenje za upravljanje robom upotrebom smartphone uređaja (dalje u tekstu DMR). Primarni cilj našeg projekta je izgradnja ...novog programskog rješenja koje će olakšati evidenciju u maloprodajnim dućanima.DMR se sastoji od nekoliko modula. Osnovni modul služi za obavljanje poslova inventure i time ubrzava popisivanje robe. Modul za inventuru robe smo dodatno proširili s funkcionalnostima pregleda stanja robe. Za potrebe upravljanja robom dok još nije stigla na maloprodajne police, razvijen je zaseban modul za evidenciju robe u skladištu. Time je zaokružen kompletan životni ciklus robe. Naknadno je razvijen i modul za veleprodajne kupce. Svi navedeni moduli se instaliraju i koriste na smartphone uređajima.Kako bi moduli DMR sustava bili povezani međusobno, kao i prema ostalim programima klijenta, razvili smo pripadajuće centralno rješenje. Centralni poslužitelj se nalazi u cloudu. Služi za integraciju svih modula te kao poveznica prema bazama podataka robom. Dodatno se koristi i kao izvještajni alat.
Posljednjih godina digitalna aerofotogrametrija počinje se primjenjivati kao alternativna metoda zračnomu laserskomu skeniranju u trodimenzionalnom modeliranju šumskih površina, poglavito u izradi ...digitalnih modela površine (DSM-ova). Za potrebe inventure šuma DSM se uglavnom koristi u kombinaciji s digitalnim modelom reljefa, preklapanjem kojih se dobije digitalni model visine sastojina/krošanja (CHM) koji se potom koristi za procjenu različitih varijabli pojedinačnih stabala ili šumskih sastojina.
Glavni je cilj ovoga istraživanja bio ispitati vertikalnu točnost DSM-ova različite prostorne rezolucije na šumskom području. U tu su svrhu za nizinske šume hrasta lužnjaka (GJ Kunjevci, UŠP Vinkovci) izrađeni DSM-ovi prostorne rezolucije 0,3 m (DSM0,3), 0,5 m (DSM0,5), 1 m (DSM1), 2 m (DSM2) i 5 m (DSM5) metodom slikovne korelacije digitalnih stereoaerosnimaka. Vertikalna točnost DSM-ova ispitana je usporedbom nadmorske visine 294 vrha stabala izmjerena manualnom, stereofotogrametrijskom izmjerom i nadmorske visine očitane s DSM-ova.
Prema očekivanjima najveća je točnost dobivena za DSM0,3 (drugi korijen srednje kvadratne pogreške, RMSE = 0,76 m; srednja pogreška, ME = –0,03 m), ali je gotovo identična točnost dobivena i za DSM0,5 (RMSE = 0,76 m; ME = –0,05 m) i DSM1 (RMSE = 0,76 m; ME = –0,07 m). Nešto manja točnost dobivena je za DSM2 (RMSE = 0,84 m; ME = –0,16 m), a najmanja točnost dobivena je za DSM5 (RMSE = 1,31 m; ME = –0,54 m).
Dobiveni rezultati pokazuju da smanjivanje prostorne rezolucije rasterskih DSM-ova od 0,3 m do 1 m ne utječe bitno na njihovu vertikalnu točnost, odnosno na točnost pri očitavanju nadmorske visine vrhova stabala. Daljnjim smanjivanjem prostorne rezolucije prema 2 m, a osobito do 5 m, vertikalna točnost DSM-ova se smanjuje. Buduća istraživanja vrijedilo bi usmjeriti na ispitivanja mogućnosti primjene DSM-ova različite prostorne rezolucije u inventuri šuma, i to: DSM0,3 i DSM0,5 za pridobivanje informacija na razini pojedinačnih stabala, DSM0,5 i DSM1 na razini plohe te DSM1, DSM2 i DSM5 na razini sastojine.
Predmet bavljenja ovoga rada je prevencija krađa i prijevara u
trgovačkim društvima tj. Retail Loss Prevention. Ovo je praksa koja je u trgovačkim društvima nastala najprije na području SAD-a te se ...kasnije proširila na Ujedinjeno Kraljevstvo uslijed osobitosti anglosaksonskog pravnog sustava. Ova praksa je novost u kontinentalnoj Europi pa tako i Republici Hrvatskoj. U Republici Hrvatskoj se ovom problematikom dosad nije ozbiljnije bavilo. Osvrnut ćemo se tako na unutarnje krađe počinjene od vlastitih djelatnika u trgovinama koje iznose 40,9% ukupnih gubitaka u trgovinama, zatim na vanjske krađe počinjene od kupaca i ostalih posjetitelja trgovina koje iznose 33,1% udjela te na ljudske/administrativne pogreške koje iznose 15.3% udjela. Kod
unutarnjih krađa na primjerima ćemo objasniti „sweathearting“,
te funkcije „no sale“ i „storno“ koje koriste djelatnici u trgovinama
na modernim POS blagajnama kako bi otuđivali novac. Bavit ćemo se također i reklamacijama i popustima za djelatnike kao metodama za krađu. Nadalje ćemo se baviti unutarnjim istraga krađa, pronevjera i prijevara u trgovačkim društvima, metodama prikupljanja dokaza, a posebice na ispitivanje osumnjičenika i svjedoka, kao i korištenjem CCTV-a (video nadzora) u istragama.
Zadatak inventure šuma je kvalitetno prikupljanje informacija, što predstavlja temelj za donošenje pravilnih odluka u gospodarenju šumama. Uz uobičajene terestričke načine prikupljanja podataka, ...podaci o šumama sve se više prikupljaju i metodama daljinskih istraživanja, čijom se primjenom smanjuje opseg terenskog rada te otvara mogućnost uštede vremena i novca. Cilj rada je dati pregled dosadašnjih istraživanja te mogućnosti primjene metoda daljinskih istraživanja u inventuri šuma u Hrvatskoj. Dosadašnja istraživanja prikazana u radu dat će uvid u sadašnje stanje i ulogu daljinskih istraživanja u inventuri šuma u Hrvatskoj, a zajedno s novim spoznajama mogu poslužiti kao smjernice za buduća istraživanja i primjenu novih metoda daljinskih istraživanja u inventuri šuma.
Cilj rada je istražiti i prikazati neke mogućnosti primjene geo statistike u uređivanju šuma u svrhu unaprjeđivanja dosadašnjeg pristupa ko rištenja i kartiranja podataka uređajne inventure šuma ...Republike Hrvatske. Geostatistička analiza podataka uređajne inventure šuma provedena je na di je lu gospodarske jedinice “Banov Brod”, šumarije Pitomača za tri strukturna ele menta: broj stabala (N), temeljnicu (G) i obujam (V).
Kontinuirana karta raspodjele vrijednosti strukturnih elemenata izrađena je metodom običnog kriginga i inverzne udaljenosti. Dobivene karte ukazuju da je procjenjivanje krigingom pouzdanije od metode inverzne udaljenosti. U radu je prikazana korisnost geostatističkih alata (semivariogramska površina, semivariogram, semivariogramski oblak) u analizi podataka uređajne inven ture šuma i njihove prostorne zavisnosti. Geostatističkim pristupom može se pro matrati bilo koja varijabla pridobivena tijekom uređajne inventure, po vrsti drveća ili ukupno, a omogućava svrsishodnije i racionalnije korištenje ovih in-for macija u prostoru i vremenu u svrhu boljeg gospodarenja šumama.
Cilj ovoga istraživanja bio je provjeriti i potvrditi opravdanost i primjenjivostvišefaznog uzorka u inventarizaciji šumskog prostora. U tu svrhu odabran je lokalitet u UŠP Split, Šumarija Zadar, GJ ...Zadarski otoci, otok Ugljan. Na izabranom lokalitetu istraživano je kako se sa što manjim intenzitetom uzorkovanja, upotrebom višefaznog uzorka mogu dobiti odgovarajući rezultate procjene sastojinskih strukturnih elemenata, koji mogu poslužiti u uređajnoj inventuri šuma. Izrađeni su digitalni model reljefa (DMR) i digitalni ortofoto (DOF), na kojem su se izlučivali različiti stratumi i planirala mreža uzoraka po fazama: I. faza-fotointerpretacija; II. faza-izbor jedinice uzorka za aerofototaksaciju; III. faza-izbor jedinice uzorka za terestričku izmjeru). Na temelju interpretacije izlučenih stratuma na digitalnom ortofotu (DOF) mo`e se planirati mreža uzoraka
u drugoj i trećoj fazi Rezultati istraživanja potvrdili su primjenjivost vi{efaznih uzoraka uz prethodno dobro isplanirani izvedbeni plan svih faza rada u svakoj utvr|enoj fazi uzorka.
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