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In the current study, the internal burnishing process under the minimum quantity lubrication (MQL) condition has been optimized to decrease the cylindricity (CYL) and circularity (CIC) of the burnished hole, while the surface roughness (SR) is predefined as a constraint. The optimizing inputs are the diameter of the spray nozzle (D), the spray elevation angle (A), the lubricant quantity (Q), and the pressure value of the compressed air (P). The artificial neural network (ANN) models of burnishing performances are proposed to optimise inputs. The grey relational analysis (GRA) is utilized to compute the weight value of each response. Optimal values of MQL system parameters and technological objectives are selected with the aid of an evolution algorithm (vibration and communication particle swarm optimization (VCPSO) algorithm). The results indicated that the optimal outcomes of the D, A, Q, and P are 1.5 mm, 50 deg, 140 ml/h, and 0.6 MPa, respectively. Furthermore, the CYL, CIC, and SR were decreased by 53.14 %, 57.83 %, and 72.97 %, respectively, at the optimal solution. Finally, the obtained results are expected to be a significant solution to support the machine operator in selecting the optimal MQL system parameters to improve the hole quality in the MQL-assisted burnishing process.

Uvod: Čiščenje posode je vsakodnevno opravilo v gospodinjstvu, ki mu velika večina ljudi ne namenja posebne pozornosti. Le malokdo pred uporabo detergenta prebere navodila za uporabo, ampak detergent dozira po lastnem občutku. Tako lahko čistilno sredstvo predoziramo in s tem povečamo količino ostankov na posodi, kar lahko škodljivo vpliva na naše zdravje. Namen: Namen magistrskega dela je določiti koncentracijo ostankov površinsko aktivne snovi natrijevega dodecil sulfata in biocida 1,2-benzizotiazol-3(2H)-ona na posodi po ročnem čiščenju, ugotoviti, ali hrapavost materiala ter globina posode vplivata na koncentracijo ostankov teh dveh kemikalij na posodi ter preveriti, ali imata v izbranih koncentracijah škodljive učinke na testne organizme. Metode dela: Koncentracijo natrijevega dodecil sulfata smo določili s pomočjo spektrofotometra po dodatku metilenskega modrila, medtem ko smo za določanje 1,2-benzizotiazol-3(2H)-ona uporabili tekočinski kromatograf. Po ugotovljenih koncentracijah ostankov obeh kemičnih snovi smo s pomočjo instrumenta LUMIstox izmerili njuno strupenost na luminiscenčne bakterije Vibrio fischeri. Rezultati: Rezultati so pokazali, da na površini krožnikov in lončkov iz lesa ostane več natrijevega dodecil sulfata in 1,2-benzizotiazol-3(2H)-ona kot na površini krožnikov in lončkov iz plastike, porcelana, nerjaveče pločevine in stekla. Ostanki natrijevega dodecil sulfata so bili na površini lončkov v povprečju za 30 % višji od koncentracije ostankov na površini krožnikov, ostanki 1,2-benzizotiazol-3(2H)-ona pa so za 60 % višji pri lončkih. Tako smo potrdili, da je več ostankov na bolj hrapavih površinah in na globljih posodah. S strupenostnim testom smo ugotovili, da koncentracija ostankov natrijevega dodecil sulfata po ročnem čiščenju povzroči od 1,7 % do 2,8 % zaviranja luminiscence pri bakterijah Vibrio fischeri, koncentracija ostankov 1,2-benzizotiazol-3(2H)-ona pa od 7,1 % do 11,5 % zaviranje luminiscence. Največjo strupenost smo zaznali pri koncentraciji obeh snovi, ki je bila v banjici, v kateri smo prali posodo (99 % zaviranje luminiscence). Razprava in zaključek: Zaradi povečanega adsorbiranja ostankov detergenta na površino posode na bolj hrapavih površinah in na globljih posodah predlagamo, da posodo po čiščenju dobro speremo z večjo količino vode, saj bomo s tem odstranili večji delež ostankov čistilnega sredstva z njene površine. Doziranje detergenta je potrebno upoštevati po navodilih proizvajalca, saj edino tako lahko preprečimo škodljive vplive na zdravje človeka. Introduction: Cleaning dishes is a daily activity in every household, which does not receive special attention by most people. Only a few of them actually read the instructions before using the detergent and usually people do not dose it. In such cases, the misusage of the cleaning agent could lead to elevated amounts of residues on the dishes, that could have some harmful effects on our health. Purpose: The purpose of our research was to determine the residual amount of surfactants – sodium dodecyl sulphate and 1,2-benzisothiazol-3(2H)-one on different materials after manual dishwashing. Besides, it was our task also to study the effect of roughness of the material on the amount and toxicity of sodium dodecyl sulphate and 1,2-benzisothiazol-3(2H)-one. Methods: To determine the amount of residue of sodium dodecyl sulphate a spectrophotometric method employing methylene blue was applied, whereas for the 1,2-benzisothiazol-3(2H)-one determination high performance liquid chromatography was used. After determining the residues of both chemicals, the toxicity measurements were done by LUMIstox instrument by measuring the toxicity of residues on luminescent Vibrio fischeri bacteria. Results: The results showed that on the wooden plate and cup there were higher residues of both sodium dodecyl sulphate and 1,2-benzisothiazol-3(2H)-one, compared to other materials like: plastic, porcelain, stainless steel and glass plate and/or cup. The residues of sodium dodecyl sulphate were on average higher by 30 % on cups, compared to plates while residues of 1,2-benzisothiazol-3(2H)-one were higher by 60 %. That proved that the rougher is the material and the deeper is the dish, the more residues remain on them. The amount of remaining sodium dodecyl sulphate on dishes after manual dishwashing caused from 1,7 % to 2,8 % inhibition of luminescence of Vibrio fischeri bacteria, while the amount of 1,2-benzisothiazol-3(2H)-one caused 7,1 % to 11,5 % inhibition. The highest percent of luminescence inhibition (99 %) was detected in the water in which the dishes were washed indicating the synergistic effect of inhibition of both compounds 1,2-benzisothiazol-3(2H)-one and sodium dodecyl sulphate, which are usually discharged in normal household waste waters. Discussion and conclusion: Due to higher detergent and biocide residues in case of rougher materials and deeper dishes, it is suggested that higher volumes of water are used for the final washing procedure, since this will result in removing a larger portion of the cleaning agent from the surface of the dish. The key element is also the dosing of detergent which should be done according to the instructions from the manufacturer. In this way, some side harmful effects on public health from dishwashing could be avoided.

Namen diplomske naloge je ugotoviti vpliv goriva na dva osnovna dela sistema za vbrizgavanje goriva: visokotlačna tlačilka in vbrizgalna šoba. Vpliv smo določili z eksperimentom merjenja pretočnega števila šob in hrapavosti sestavnih delov tlačilke. Meritve so se izvajale z dvema različnima testiranima mešanicama goriv, hkrati, pri enakih pogojih (tem., tlak…), in sicer z uporabo 85% dizelskega goriva ter 15% bioetanola (D85E15) in z uporabo 85% biodizelskega goriva ter 15% bioetanola (B85E15). Rezultati samih meritev so pokazali, da samo gorivo vpliva na obrabo delov vbrizgalnega sistema. The main purpose of this Diploma thesis is to determine the influence of the fuel on two different fuel injection systems: High-pressure pump and Injectable nozzle. The impact of the fuel has been analysed by measuring the flow rate of nozzles and roughness of the pump components.The measurements have been conducted at the same conditions (temperature, pressure ...etc.), on the basis of two different fuel mixtures: 85% of diesel and 15% of bio ethanol (D85E15) and 85% of bio diesel and 15% of bio ethanol (B85E15). The results of the measurements have shown and confirmed that the fuel itself have a considerable influence on ware of the injecttable system parts.