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Öğe An Application to Control Media Player with Voice Commands(Gazi Univ, 2020) Avuclu, Emre; Ozcifci, Ayhan; Elen, AbdullahUsing technology today is of great importance in terms of making people's lives easier. It has become very easy to run some applications with technology. In this study, an application that provides media player control with voice commands was developed. This application was developed to address the needs of people who cannot listen to music on their own due to any disability. The application was implemented in C# programming language. In order to manage the media player with voice commands, voice recognition libraries were first used. In the developed application, operations with keyboard and mouse can be done with voice commands. Voice commands can be sent with the wireless headset from anywhere in the shooting area.Öğe BIO-OIL PRODUCTION FROM CATALYTIC PYROLYSIS METHOD OF FURNITURE INDUSTRY SAWDUST(Gazi Univ, Fac Engineering Architecture, 2013) Ozcifci, Ayhan; Ozbay, GunayIn this study, scots pine (Pinus sylvestris L.) sawdust was used as biomass resources. Catalyzed and uncatalyzed (thermal) pyrolysis processes were conducted in a fixed-bed reactor. The effects of the parameters on pyrolysis product yields such as temperature and catalysis type were investigated. The pyrolysis of the experimental samples that have a particle size in the range of 0.850-1.60 mm were carried out at the temperatures of 400, 500 and 600 degrees C at the heating rate of 5 degrees C/min. Nitrogen gas (N-2) flow was used at the rate of 30 ml/min during the process. Basic salts such as Na2CO3, K2CO3 and Lewis acid (FeCl3) were used as catalyses. As a result, it was determined that temperature and catalysis types were effective parameters in the yields of char, bio-oil and gas products. Also it was determined that the conversion of wood materials into fuel or valuable chemicals with the pyrolysis method is an applicable technology.Öğe Catalytic pyrolysis of waste melamine coated chipboard(Wiley-Blackwell, 2013) Ozbay, Gunay; Ozcifci, Ayhan; Karagoz, SelhanCatalytic pyrolysis of waste melamine coated chipboard was performed in a fixed-bed reactor at 400 degrees C, 500 degrees C, 600 degrees C, and 700 degrees C and a residence time of 1 h. The effects of temperature and catalysts on both product distribution and bio-oil composition were discussed. Lewis acids (AlCl3, TiCl4, and FeCl3), bases (NaOH and KOH), and basic salts (Na2CO3 and K2CO3) were used as catalysts in the pyrolysis process. The product distributions were changed depending on both the type of catalyst and temperature. Bio-oil obtained from the pyrolysis of melamine coated chipboard contained a large variety of oxygenated hydrocarbons. Phenols were found to be the major compounds identified in bio-oils for all tested runs. The bio-oils produced by Lewis acids contained aldehydes. However, the bio-oils obtained from the thermal run, the run with bases, and the run with basic salts did not contain these compounds. (c) 2011 American Institute of Chemical Engineers Environ Prog, 32: 156161, 2013.Öğe Determination of diagonal compression and tension performances for case furniture corner joints constructed with wood biscuits(Elsevier Sci Ltd, 2009) Atar, Musa; Ozcifci, Ayhan; Altinok, Mustafa; Celikel, UzeyirThis study was carried out to determine the performance of different wood biscuits on the diagonal compression and tension strength for case-type furniture corner joints. For this purpose, melamine-coated particleboard (MCP) and melamine-coated fiberboard (MCF) panels were bonded with polyvinyl acetate (PVAc)and Desmodur VTKA (DVTKA) adhesives on miter joint (Mj) and butt joints (Bj). The diagonal compression and tension strength tests were done according to ASTM D 1037 standards. As a result, the highest diagonal compression and tension strength were obtained in MCF with DVTKA adhesive, As for the interactions, panel + adhesive + corner joints, the highest value was MCF + DVTKA + miter joint in both compression and tension tests. According to these, it is advised that the member of the wood biscuits produced from solid woods is used in the corner joints in case furniture. (C) 2008 Elsevier Ltd. All rights reserved.Öğe Determination of Effects of Waste Boron Oil on Some Physical Properties of Wood(Kastamonu Univ, Orman Fak, 2010) Ozcifci, Ayhan; Batan, FarukIn this study, it was aimed to determine some physical properties of Uludag fir (Abies bornmulleriana Mattf.), oriental beech (Fagus orientalis Lipsky) and Scots pine (Pinus sylvestris L.) woods impregnated with waste of boron oil. For this purpose, the samples were impregnated with two different methods according to ASTM-D 1413 standards. In the first method, full cell method, for an hour the wood materials were vacuumed for an hour and then they were impregnated under 4 atm for an hour. As for the second method, test samples were immersed in waste boron oil for an hour. The result of the experiments show that the highest amount of retention, retention ratio, unburnt pieces and ash were observed on Scotch pine samples by using immersing method, the highest density, temperature, CO2 and CO were observed in beech samples by using pressure method. The highest weight loss was occurred on beech pressure control and the highest O-2 ratio was observed on Abies control test samples. As a conclusion, the wood material should be impregnated by pressure method if it is to be used in the fields which will be exposed to physical pressure.Öğe DETERMINATION OF FATIGUE AND STATIC STRENGTH OF SCOTS PINE AND BEECH WOOD(Slovak Forest Products Research Inst, 2015) Yildirim, Mehmet Nuri; Uysal, Burhanettin; Ozcifci, Ayhan; Ertas, Ahmet H.In this study, fatigue and static strength of Scots pine (Pinus sylvestris L.) and beech (Fagus orientalis L.) woods were investigated. The fatigue and static strength were conducted using a three point bending test-rig. The specimens were prepared according to ISO 3129 (1975) and fatigue and static bending test were carried out according to ISO 3133 (1975). The fatigue test was carried out at 80, 70, 60, 50 and 40 % stress level that corresponded to specific percentage of material's ultimate strength modulus of rupture (MOR). However the microstructures of fatigue failures were observed by using scanning electron microscope (SEM). The results were indicated that, the fatigue life of Scots pine wood amounted to over 1 million cycle when the stress level was 40 % of MOR for Scots pine and 50 % MOR for Beech. In general, fatigue life decreased as stress level increased and vice versa. The allowable design stress is based on some percentage of MOR for furniture design. On this account, the allowable design stresses for Beech and Scots pine could be set at 50 and 40 % respectively.Öğe Determination of modulus of rupture and modulus of elasticity on flakeboard with fuzzy logic classifier(Elsevier Sci Ltd, 2009) Yapici, Fatih; Ozcifci, Ayhan; Akbulut, Turgay; Bayir, RaifIn this study, a model based on fuzzy logic classifier was created in order to determine the values of modulus of elasticity (MOE) and modulus of rupture (MOR) of flakeboards. MOR and MOE are the most important mechanical features of wood-composite panels. The most appropriate mixture ratios to be used in production of wood based boards were determined experimentally. These experiments are very expensive for the manufacturers and require time. For this purpose, MOE and MOR values were measured depending on flakes mixture ratios of manufactured boards. Using these values, input and output values and rule base of fuzzy logic classifier were created. With the fuzzy logic classifier model prepared in Matlab Simulink, MOR and MOE values for flakes mixture ratios were predicted. It was observed that the fuzzy logic classifier predicted MOR and MOE values with 95-97% accuracy. With this system, for the manufacture of wood-composite materials, the most appropriate chip mixture amount required by the manufacturer could be determined. (C) 2008 Elsevier Ltd. All rights reserved.Öğe Determination of some physical and mechanical properties of laminated veneer lumber impregnated with boron compounds(John Wiley & Sons Inc, 2007) Ozcifci, Ayhan; ors, Yalcin; Uysal, BurhanettinThe aim of this study was to determine the effects of Tanalith-C 3310 (T-C 3310), borax (Be), boric acid (Ba), borax + boric acid (Bo + Ba), and diammonium phosphate (D) impregnations for some physical and mechanical properties of laminated veneer lumber (LVL). The veneers used for the LVL samples (based on BS EN 204) were cut from Scots pine (Pinus sylvestris L.), oriental beech (Fagus orientalis L.), and poplar (Populus nigra). They were impregnated with full-cell method according to ASTM-D 1413 standards and bonded with phenol formaldehyde (PF) and melamine formaldehyde (MF) adhesives. The following parameters have been tested: density, compression strength, bending strength, modulus of elasticity (MOE) in bending, and shear strength tests. Test results obtained from this study showed that impregnation with Boric acid and Tanalith-C 3310 (based acidic characteristic) affected the strength of LVL negatively, when the wood material is impregnated with acidic impregnations and bonded with PF, which is an alkali, the glue-line becomes more elastic, the bonding strength of adhesive weakens. Boric acid and Tanalith-C 3310 impregnations could not be recommended for LVL elements exposed to bending or shear strength. (c) 2007 Wiley Periodicals, Inc.Öğe THE EFFECT OF GRAIN ANGLE AND SPECIES ON THERMAL CONDUCTIVITY OF SOME SELECTED WOOD SPECIES(North Carolina State Univ Dept Wood & Paper Sci, 2011) Yapici, Fatih; Ozcifci, Ayhan; Esen, Rasit; Kurt, SerefIn this study the thermal conductivity of different wood materials was determined. For this purpose, Scots pine (Pinus sylvestris L.), Uludag fir (Abies Bornmulleriana Matff), Oriental beech (Fagus orientalis L), Oak (Quercus robur L.), and Chestnut of Anatolia (Castanea sativa Mill.) woods were used. In the test, the thermal conductivity of the woods was measured according to procedure of ASTM C 1113-99 standards. The lowest thermal conductivity was obtained in the perpendicular direction of Scots pine samples as 0.156 Kcal/mh degrees C. The highest thermal conductivity was obtained from perpendicular direction of samples in Oriental beech as 0.331 Kcal/mh degrees C.Öğe The effect of heat treatment on bio-oil properties obtained from pyrolysis of wood sawdust(Springer, 2015) Ozbay, Gunay; Pekgozlu, Ayben Kilic; Ozcifci, AyhanHeat treatment is becoming increasingly popular and is growing as an industrial process to improve wood properties. The Finnish wood heat treatment technology, ThermoWood, is the most commonly used technology in the industrial area. In this study, pyrolysis of untreated and heat-treated ash wood (Fraxinus excelsior L.) was carried out using a fixed-bed reactor at different pyrolysis temperatures. The influences of the heat treatment process and the pyrolysis temperature on the yields and chemical composition of products were investigated. The maximum bio-oil yield was 46 wt% at a pyrolysis temperature of 550 degrees C for untreated wood, while the biooil yield was found to be about 41 wt% at a pyrolysis temperature of 500 degrees C for heat-treated wood. The elemental composition and higher heating value (HHV) of the bio-oil was determined. The chemical composition of the bio-oil was investigated using some chromatographic and spectroscopic methods, such as gas chromatography-mass spectrometry (GC/MS) and 1 H-NMR. It was found that the heat treatment process significantly reduced the organic acids, ketones and aldehydes, while it increased the phenolic compounds. These results show that heat-treated wood sawdust should be used as a valuable feedstock for production of the bio-oil.Öğe Effect of Some Chemicals on Thermal Conductivity of Laminated Veneer Lumbers Manufactured with Urea formaldehyde and Phenol formaldehyde Adhesives(Kastamonu Univ, Orman Fak, 2008) Sahin Kol, Hamiyet; Ozcifci, Ayhan; Altun, SuatThe objective of this research was to investigate the effects of impregnation materials on the thermal conductivity of six-layered laminated veneer lumber (LVL) made of beech and Scots pine. Zinc chloride and ammonium sulfate as impregnation chemicals and urea formaldehyde (UF) and phenol formaldehyde (PF) adhesives as bonding agent were used to produce LVLs. The veneers were impregnated by using the vacuum-pressure method. The thermal conductivity test was performed based on ASTM C 1113-99 hot-wire method. Results showed that the impregnation chemicals increase the thermal conductivity of LVLs. As impregnation chemicals, the highest value was obtained with ammonium sulfate. In addition, the thermal conductivity of LVL made of beech was higher than that of LVL made of Scots pine. The thermal conductivity of LVL bonded with FF was absolutely higher than LVL bonded with UF in both wood species.Öğe Effect of Some Mechanical Properties on Wood Materials Impregnated with Waste Boron Oil(Gazi Univ, 2009) Ozcifci, Ayhan; Batan, FarukIn this study, it was aimed to determine some physical and mechanical properties of Uludag fir (Abies bornmulleriana Mattf.), Oriental beech (Fagus orientalis Lipsky) and Scots pine (Pinus Sylvestris L.) woods impregnated with waste of boron oil. For this purpose, test samples were impregnated with two different methods according to ASTM-D 1413 standards. In the first method, full cell method, for an hour the wood materials were vacuumed for an hour and then they were impregnated under 4 atm for an hour. As for the second method, they were immersed in boron oil for an hour. The results of the experiments show that the highest amount of retention ratio and densities were observed in beech samples. In mechanical strength, the highest bending strength, modulus of elasticity, compression strength and dynamic bending strength were obtained in beech control samples. In conclusion, the wood material should be impregnated by pressure method if waste boron oil is to be used in the fields which will be exposed to physical pressure. Moreover, waste boron oil caused decreasing the mechanical properties as 2% or 5%. However, it is determined that this result is not important for properties of wood materials. According to this wood material could be impregnated by dipping method if it is to be used in the fields which will be exposed to mechanical pressure.Öğe EFFECT OF TENON GEOMETRY, GRAIN ORIENTATION, AND SHOULDER ON BENDING MOMENT CAPACITY AND MOMENT ROTATION CHARACTERISTICS OF MORTISE AND TENON JOINTS(Soc Wood Sci Technol, 2012) Likos, Erkan; Haviarova, Eva; Eckelman, Carl A.; Erdil, Yusuf Ziya; Ozcifci, AyhanBending moment capacity and moment rotation characteristics of mortise and tenon joints as a function of tenon geometry, grain orientation, length, and shoulder fit were examined. Bending moment capacity of all joints in which tenons were fully inserted in mortises was 54% greater than for joints in which tenons were not fully inserted. Joints with 25.4-mm-long diamond-shaped tenons had greater moment capacity than either rectangular or round tenon joints, whereas joints with 38- or 51-mm-long rectangular tenons had greater capacities than joints with diamond or round tenons. Similarly, for joints in which tenons were not fully inserted, rectangular tenons had the greatest moment capacity regardless of grain orientation or length.Öğe THE EFFECTS OF ADHESIVE RATIO AND PRESSURE TIME ON SOME PROPERTIES OF ORIENTED STRAND BOARD(North Carolina State Univ Dept Wood & Paper Sci, 2011) Gunduz, Gokhan; Yapici, Fatih; Ozcifci, Ayhan; Kalaycioglu, HulyaThis study was carried out to determine the effects of adhesive ratio and pressure time on thickness swelling (TS), internal bond (IB), modulus of rupture (MOR), and modulus of elasticity (MOE) properties of oriented strand board (OSB). For this purpose, 80 mm long strands made of Scots pine (Pinus sylvestris L.) were bonded with phenol-formaldehyde resin at three different ratios (3, 4.5, and 6%) to produce three-layer cross-aligned OSBs. Strands used for the production of OSB panels were made up 40% of core layer and 60% of outer layers. The panels were pressed for three different press times, from 3, 5, to 7 minutes, under 0.4 MPa pressure, aiming for a target density of 0.70 g/cm3. TS, IB, MOR, and MOE properties of OSB panels were evaluated according to the standards (TSE EN 117-319-310). Results showed that MOR and MOE values were changed in the ranges 25.31 to 42.27 N/mm(2), and 2848.90 to 6545.63 N/mm(2), respectively. Also, the results showed that as adhesive ratio and pressure time increased, the TS, MOR, and MOE values increased too.Öğe Effects of application methods and species of wood on color changes of varnishes(Academic Journals, 2009) Budakci, Mehmet; Ozcifci, Ayhan; Cinar, Hamza; Sonmez, AbdullahIn this study, the color effects of wood materials to coloring with different application methods (brush, roller sponge and spray gun) and waterborne varnishes were investigated according to ASTM-D 2244. For this purpose, the experimental samples of Scots pine (Pinus silvestris L.), oriental beech (Fagus orientalis L.) and oak (Quercus petreae L.), which are commonly used woods in the carpentry and furniture industry in Turkey, were prepared and varnished with one and two-pack waterborne varnishes in accordance with ASTM D 3023. According to the result of the research, significant color changes in coloring as red and yellow tones on the sample surfaces of varnished wood materials were found. The highest color change was obtained in the samples of oak, when varnished with brush and spray gun while the lowest value was obtained in roller sponge in respect to the application methods for waterborne varnishes. However, the application method of spray gun for self crosslinked polyurethane, topcoat-clear, (SCPt) gave the highest metric chroma value among the three different application methods.Öğe Effects of Catalysts on Modulus of Rupture and Chemical Structure of Heat-Treated Wood(Zagreb Univ, Fac Forestry, 2018) Ozcifci, Ayhan; Kokten, Erkan Sami; Ayrilmis, Nadir; Ozbay, Gunay; Altun, SuatHeat treatment process, which is widely used in the wood industry, has shown some negative effects on the mechanical strength of wood. The objective of this study was to investigate the effects of catalysts on the modulus of rupture (MOR), mass loss and chemical structure of heat-treated Scotch pine (Pinus sylvestris L.) samples. For this purpose, some catalysts (50 % NaOH and 47 % KOH solutions, solid KOH) were added to the heat treatment process. Heat treatment experiments were performed under the nitrogen atmosphere at the temperature of 212 degrees C for 2 h. The MOR and chemical changes monitored by FT-IR spectra were then examined for the test groups. According to the results of this study, the use of commercial solid potassium hydroxide (KOH) in heat treatment decreased the degree of strength loss and mass loss of heat-treated wood. The strength (MOR) loss of samples heat-treated in the presence of potassium hydroxide was found to be only 5.4 %, while the strength loss in non-catalytic treatment was found to be 12.5 %.Öğe Effects of heat treatment and surface roughness on bonding strength(Elsevier Sci Ltd, 2012) Ozcan, Suleyman; Ozcifci, Ayhan; Hiziroglu, Salim; Toker, HilmiThe objective of this study was to determine the effect of heat treatment on bonding strength of the samples from four different species, namely Scotch pine, oriental beech, white oak and Uludag fir woods. The samples were exposed to three temperature levels of 120 degrees C, 150 degrees C and 180 degrees C for time periods of 2 and 6 h. Based on the findings in this work white oak samples had the highest average roughness (R-a) and maximum roughness (R-max) values of 9.49 mu m and 48.9 mu m, respectively. It appears that heat treatment enhanced overall surface quality of the samples. (C) 2012 Elsevier Ltd. All rights reserved.Öğe Effects of machining method and grain orientation on the bonding strength of some wood species(Elsevier Science Sa, 2008) Ozcifci, Ayhan; Yapici, FatihThis study was conducted to determine the effects of various machining methods and grain orientation on bonding strength of some wood species. For this purpose, Oriental beech (Fagus orientalis Lipsky.), Oak (Quercus robur), Scotch pine (Pinus sylvestris L.), Poplar (Populus tremula L.) and Uludag fir (Abies bornmulleriana Matff.) were used as raw materials. Phenol-formaldehyde (PF), poly (vinyl-acetate) (PVAc), polyurethane based Desmodur-VTKA (D-VTKA) and urea-formaldehyde (UF) adhesives were applied to one surface of the test samples. Bonding strength tests (based on TS EN 205) were applied on the connection surface. The test samples were machined with circular saw, band saw and thickness planer. The results indicated that the highest bonding strength was obtained from Oriental beech wood samples bonded with PVAc adhesive (14.83 N/mm(2)), while Poplar samples bonded with D-VTKA had the lowest values (2.99 N/mm(2)). In addition, the machined surface of the tangential direction had higher bonding strength than that of the radial direction. (C) 2007 Elsevier B.V. All rights reserved.Öğe Effects of Outdoor Exposures and Boron Compounds on Bonding Strength of Desmodur-VTKA Adhesive(Taylor & Francis Ltd, 2010) Ozcifci, AyhanThis study was carried out to determine the shear strength of an adhesive on weathered wood, impregnated with a boron compound, using a long term dipping method. The shear strength of D-VTKA adhesive on two types of wood species each containing one of two types of the impregnated material, under different weathering conditions, was measured. The results showed that the highest shear strength (11.01 N/mm(2)) was obtained with the control samples of untreated, oriental beech wood, and the lowest was obtained for Scots pine impregnated with boric acid after two seasons of exposure (six months). Weather conditions affected the shear strength in a negative way. Finally the results showed that if the boron compounds were supported with non-leaching chemicals, they could be recommended as fire-retardant additives and would extend the life of wood bonded with D-VTKA adhesive. (C) Koninklijke Brill NV, Leiden, 2010Öğe The effects of pilot hole, screw types and layer thickness on the withdrawal strength of screws in laminated veneer lumber(Elsevier Sci Ltd, 2009) Ozcifci, AyhanThe objective of this study was to evaluate the effects of screw type, pilot hole and layer thickness on the withdrawal strength of some screws in laminated veneer lumbers (LVL). For this purpose, three, four and five layered laminated samples were produced in different veneer thickness (4, 5 and 7 mm) of Uludag fir (Abies bornmulleriana Mattf.) and oak (Quercus petraea spp.) woods. And melamine-formaldehyde (MF) and phenol-formaldehyde (PF) adhesives were also used for laminated veneer lumber manufacturing. Withdrawal strength test was applied on the test samples. According to the test results, it was found that the highest withdrawal strength was obtained in oak samples having 4 mm veneer thickness bonded with PF for 3.5 x 16 screw as 23.14 MPa, the lowest was obtained for Uludag fir having 5 mm veneer thickness bonded with MF adhesive with 4.0 x 50 screw as 7.61 MPa. The use of proper size of pilot holes is advised in order to avoid splitting of the face during insertion of screws as well as to obtain maximum withdrawal strength. (c) 2008 Elsevier Ltd. All rights reserved.
