| | SLO | ENG | Cookies and privacy

Bigger font | Smaller font

Show document Help

Title:Napovedovanje kemične sestave krme z NIR spektroskopijo
Authors:ID Štalekar, Alenka (Author)
ID Prevolnik Povše, Maja (Mentor) More about this mentor... New window
Files:.pdf VS_Stalekar_Alenka_2015.pdf (770,90 KB)
MD5: 9BA045F068CA5448BBF693A3223916F4
 
Language:Slovenian
Work type:Bachelor thesis/paper
Organization:FKBV - Faculty of Agriculture and Life Sciences
Abstract:V diplomskem delu smo preučevali uporabnost prenosnega NIR spektrometra za napovedovanje kemične sestave krme. V raziskavo smo vključili 244 vzorcev travnih silaž, mrve in zelene krme, v katerih smo z weendsko analizo določili vsebnost suhe snovi (SS), surovih beljakovin (SB), maščob (SM), vlaknine (SV) in pepela (SP) ter prostornino plinov (ki je pomembna za izračun energijske vrednosti krme). Dobljene kemične analize smo povezali s spektralnimi podatki. Pri razvijanju in validaciji modelov smo testirali vpliv območja valovnih dolžin, uporabe odvodov osnovnega spektra absorbcije ter načina validacije modelov. Kakovost modelov smo ovrednotili z determinacijskim koeficientom (R2CV) in napako navzkrižne validacije (seCV) ter parametrom RPD (razmerje med seCV in standardnim odklonom referenčnih vrednosti). V splošnem smo dobili boljšo kakovost modelov brez uporabe odvodov na celem in NIR spektru. Način validacije ni imel vpliva na rezultate. Zelo dobre rezultate smo dobili za SB (R2CV >0,90, RPD > 3,0) in SV (R2CV > 0,85, RPD>2,5) ter srednje dobre za SM, SP in prostornino plinov (R2CV = 0,65-0,75, RPD = 1,5-2,0). SS nismo uspeli zadovoljivo napovedati. Za primerjavo smo modele razvili še z laboratorijskim spektrometrom. Kakovost modelov pri laboratorijskem inštrumentu je bila večja kot pri prenosnem spektrometru. Razlog za to je delno v slabši natančnosti prenosnega inštrumenta (optična sonda in kabel) in delno v časovni razliki med izvedbo kemijske in spektralne analize pri prenosnem inštrumentu. Upoštevajoč slednje lahko zaključimo, da ima prenosni NIR spektrometer velik potencial za napovedovanje kemične sestave krme, vendar bi bilo za praktične namene potrebno napovedne modele pripraviti ponovno z novimi vzorci krme.
Keywords:NIR spektroskopija, krma, kemična sestava, prenosni spektrometer
Place of publishing:Maribor
Year of publishing:2015
PID:20.500.12556/DKUM-55187 New window
NUK URN:URN:SI:UM:DK:QRI33ASS
Publication date in DKUM:19.10.2015
Views:3575
Downloads:272
Metadata:XML DC-XML DC-RDF
Categories:FKBV
:
Copy citation
  
Average score:(0 votes)
Your score:Voting is allowed only for logged in users.
Share:Bookmark and Share



Hover the mouse pointer over a document title to show the abstract or click on the title to get all document metadata.

Secondary language

Language:English
Title:Predicting chemical composition of forage using NIR spectroscopy
Abstract:The aim of the present study was to assess the ability of portable NIR spectrometer to predict chemical composition of forage. The study comprised 244 samples of grass silage, hay and green grass, in which dry matter, protein, fat, raw fibres, ash and gas volume (which is important to calculate energy value) were analysed using Weende analysis. When developing and validating models different parameters were tested: spectral region, derivatives of original spectrum and the type of validation. The quality of models was assessed through coefficient of determination (R2CV) and standard error of cross-validation (seCV) and RPD parameter (ratio between seCV and standard deviation of reference values). In general, the highest quality of models was obtained without using derivatives on the whole or NIR spectral range. The type of validation did not affected the results. Very good results were obtained for protein (R2CV > 0.90, RPD >3.0) and raw fibres (R2CV >0.85, RPD>2.5) and a little less accurate for fat, ash and gas volume (R2CV =0.65-0.75, RPD =1.5-2.0). Dry matter content could not be satisfactory predicted. Obtained results were compared with those obtained with laboratory spectrometer. The latter gave models of better quality. This could be partly explained by lower accuracy of portable instrument (optical sonda and cable) and party by time span between chemical and spectral analysis in case of portable NIR instrument. Considering the latter, it could be concluded that portable NIR spectrometer has great potential for the prediction of forage composition. However, for practical purposes the models could be prepared again using new forage samples.
Keywords:NIR spectroscopy, forage, chemical composition, portable spectrometer


Comments

Leave comment

You must log in to leave a comment.

Comments (0)
0 - 0 / 0
 
There are no comments!

Back
Logos of partners University of Maribor University of Ljubljana University of Primorska University of Nova Gorica