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Learning Management Systems (LMS) are software applications that facilitate the management and monitoring of online teaching courses and/or training programs, workshops, webinars, forums, and other similar learning activities. The LMS provides learning and teaching benefits and possibilities for synchronous, asynchronous, and hybrid training. For instance, learning management systems (LMS) can store a wide variety of large-scale educational data. The stored data can be analyzed by employing educational data mining methods. Educational data mining (EDM) is a new discipline that deals with methods for exploring the unique and large-scale data generated by digital platforms to better understand students’ learning progress and the learning environment itself. In this study, the data stored in the LMS used by Balıkesir University during the fall semester of the 2021–2022 academic year were analyzed by using educational data mining methods in order to reveal the current status of distance education activities and make suggestions to improve the quality.

Bu çalışmada, bambu liflerinden üretilen ahşap-plastik kompozit malzemenin bazı mekanik özellikleri araştırılmıştır. LDPE malzeme ile bambu liflerinin %5 ve %10 oranlarında karıştırılmasıyla ahşap plastik kompozit malzemeler üretilmiştir. Üretilen ahşap-kompozit örnekler çekme mukavemeti ve eğilme mukavemeti testlerine tabi tutulmuş ve sonuçları incelenmiştir. Sonuçlar, bambu oranı %5’ten %10’a yükseldikçe çekme mukavemeti % 6 oranında azaldığı göstermiştir. Ayrıca, bambu oranının %5’ten %10’a yükseltilmesi, her bir test grubunun ortalama eğilme mukavemetini % 44,75 oranında artırmıştır., In this study, some mechanical properties of wood-plastic composite material produced from bamboo (Bambusoideae) were investigated. Wood-plastic composite materials were produced by mixing Low Density Polyethylene (LDPE) material and bamboo fibers at the rates of 5% and 10%. The produced wood-composite samples were subjected to tensile strength and bending strength tests and the results were examined. The results showed that the tensile strength decreased by 6% as the bamboo ratio increased from 5% to 10%. In addition, increasing the bamboo ratio from 5% to 10% increased the average bending strength of each test group by 44.75%.

Aim of study: The adsorption properties of the samples of full-dry Eastern Spruce (ES) [Picea orientalis (L). Link.] with 12.5 mm, 25 mm, 37.5 mm and 50 mm thick is to determine under the climate conditions with 42%, 65% and % 78 of relative humidity and at a constant temperature of 20 °C.Material and method: The wood samples used in this study were the Eastern Spruce woods which were obtained from Forestry Process Management in the city of Trabzon/Turkey. With regard to mathematical modeling used to determine the wood moisture content (MC), the equation constants in case of adsorption was determined. Experiments were conducted at three different equilibrium moisture content (EMC); 8%, 12% and 16%.Main results: Cross section had no crucial effect on the rate of accessibility to the final MC. However, EMC and thickness have been effective.Research highlights: In practice, since dried wood is kept at outside weather conditions for a certain time before operation, an increase can be observed in the wood MC. It is practically important that under the influence of climate conditions until its utilization, the tendency of water adsorption of wood is determined as a function of time., Çalışmanın amacı: Tam kuru Doğu ladini [Picea orientalis (L). Link.] örneklerinin 12.5 mm, 25 mm, 37.5 mm ve 50 mm kalınlıkta, 20 ° C sabit bir sıcaklıkta ve % 42 ,% 65 ve %78 farklı bağıl nem koşullarında adsorpsiyon özelliklerini belirlemektir.Materyal ve yöntem: Bu çalışmada Maçka Orman İşletme Müdürlüğü’nden alınan Doğu Ladini örnekleri kullanılmıştır. Odun rutubet içeriğini belirlemek için kullanılan matematik modelleme ile adsorpsiyon durumunda denklem sabitleri belirlenmiştir. Deneyler, % 8, % 12 ve % 16 olmak üzere üç lif doygunluk noktası için gerçekleştirilmiştir.Sonuçlar: Kesitin, denge rutubetine erişilebilirlik oranı üzerinde önemli bir etkisinin olmadığı, bununla birlikte denge rutubet miktarı ve kalınlığın etkili olduğu belirlenmiştir.Araştırma vurguları: Kurutulmuş odunun, kullanım öncesinde belirli bir süre dış hava şartlarında tutulduğunda rutubet içeriğinde bir artış gözlemlenebilir. Kullanıma kadar iklim koşullarının etkisi altında, odunun rutubet alma eğiliminin zamanın bir fonksiyonu olarak belirlenmesi pratik olarak önemlidir.

Çalışmanın amacı: Bu çalışmanın amacı, Trabzon / Türkiye'de üretilen altı farklı yoğunluktave iki farklı kategoride olan poliüretan süngerlere uygulanan sürekli yorulmayüklemesi sonrası IFD sertlik ve kalınlık değerlerinde meydana gelendeğişimleri incelemektir.Materyal ve Metod: ASTM D3574 standardı baz alınarak süngerler ilk olarak IFD sertlik testine ve sürekli-yorulma testlerine tabitutulmuştur. Daha sonra, süngerlerin sürekli yükleme sonrası nihai IFD sertlikdeğerleri ölçülmüştür. Süngerlerin IFD sertlik değerlerindeki değişimler raporedilmiştir.Sonuçlar: Normal kategorideki süngerlerin yoğunluğununarttırılması sünger sertliğini gösteren IFD kayıp oranını azalmasına sebepolmuştur. Ancak, bu durum yumuşak kategorideki süngerler için tam tersidir.Bununla birlikte, normal süngerlerin destek faktörü değerleri, sürekli-yorulmayüklemesinden sonra yoğunluk arttıkça artmış, yumusak süngerler için yoğunluk arttıkçaazalmıştır. Bu çalışmada kullanılan tüm süngerler, sürekli-yorulmayüklemesinden sonra, % 10'dan daha az bir kalınlık kaybı göstermiş olup,süngerlerin görünüşlerinde görsel bir bozulma tespit edilmemiştir.Önemli vurgular: Koltuk üretiminde yumuşak bir sünger kullanılacağı zaman, sürekli yorulmayüklemesi altında yumuşak süngerlerin normal süngerlere göre teknik olaraktamamen zıt bir davranış gösterdiğini bilmek önemli olacaktır., Aim of study: The target of this study wasmeasuring the changes in IFD firmness and thickness values afterconstant-fatigue loading on the polyurethane (PUR) foams, with six differentdensities and two different categories, produced in Trabzon/Turkey. Material and Method: The foams were firstly exposedto indentation force deflection (IFD) and constant-fatigue tests based on ASTMD3574 standard. Then, the final IFD values ​​of the foams were determined afterloading and the changes in IFD values were reported. Main results: Results indicated thatincreasing the density of foam in normal category decreased the IFD loss ratein foam firmness. However, this was vice versa for the soft foams. The supportfactors of normal foams raised as density increased after constant-fatigueloading, however; the support factors of soft foams decreased as the densityincreased. All foams used in this study indicated a thickness loss lower than10% after constant-fatigue loading and, no visual failure was detected on theappearances of foams.Highlights: It is important to note that when using a softfoam in a sofa frame, it technically shows opposite behavior both in IFD lossand support factor values under constant-fatigue loading compared to normalfoam.

In this study, the cyclic fatigue performance of six different polyether type of polyurethane foams was investigated. The foams were first subjected to indentation force deflection (IFD) and 8000 cycles fatigue loading according to ASTM D3574-11. The second measurement of IFDs of the foams were carried out to observe the changes after 8000 cycles loading. Then, the foams were subjected to 80000 cycles loading. The final IFDs of the foams were measured, and the changes in the IFD, foam firmness, and thickness of the foams were determined. The results showed that increasing the density of the normal foam from 14 to 28 kg/m3 reduced the 25% IFD loss values of the foams from 30.7% to 21.5%, which increased foam firmness. However, increasing the density of the soft foam from 24 to 32 kg/m3 insignificantly increased the IFD loss values from 20% to 23.6%, which decreased the foam firmness. The support factors of both the normal and soft foams increased as the density increased after the loadings. Generally, no visual deformation was observed for the foams.

Factors influencing the vertical driving force magnitude applied to screws during the process of driving the screws into faces of particleboard materials were investigated. In particular, the screw penetration depth and screwdriver air pressure were evaluated relative to critical torques, such as seating and stripping torques. Experimental results indicated that vertical driving forces significantly affected the magnitude of critical driving torques when no pilot hole was drilled, but this influence became non-significant when 3.2-mm diameter pilot holes were drilled. Screw-driving power had no significant effect on the magnitude of critical driving torques in particleboard materials if no pilot hole was drilled, but if pilot holes were drilled, increasing the screwdriver air pressure from 0.45 to 0.62 MPa led to increases in stripping torques. Increasing the screw penetration depth from 12.7 to 19.1 mm can significantly increase seating and stripping torques.

The effect of end distance was evaluated relative to the static ultimate lateral resistance load of single-shear unconstrained metal-to-parallel bamboo strand panel (PBSP) single-bolt connections that failed in end tear-out, net cross-section tension modes. Empirical equations for estimation of the static ultimate lateral resistance loads of the evaluated connections were derived. The connection consisted of a PBSP main member fastened to a metal plate as a side member using a 6 mm diameter bolt without a nut or washer. The stress concentration factor was considered in the process of deriving the estimation equations for static ultimate lateral resistance loads. The experimental results indicated that the stress concentration factor was a linear function of end-distance to bolt-diameter ratio, (e/d), for connections that failed in end tear-out mode, while a quadratic function of (e/d) for connections that failed in net cross-section tension mode. The derived estimation equations including stress concentration factor can reasonably estimate the static ultimate lateral resistance load of single-shear unconstrained metal-to-PBSP single-bolt connections evaluated in this study.

In this study, creep characteristics of single stapled furniture joints made of Scotch pine, alder and beech wood under three different load levels were considered. Load levels were determined as 30 %, 40 % and 50 % of the maximum load obtained as a result of static shear test before creep load and applied to wood joints. Laboratory test results showed that the highest creep deformation was observed in the joints made of Scotch pine with the lowest density, while the lowest creep deformation was observed in the joints made of beech with the highest density. In addition, the joints were exposed to lowest creep deformation at the 30 % load level, then the creep deformation of the joints increased at 40 % load level and it reached the highest value at 50 % load level. As a result of creep test, deformation in single stapled joints made of Scotch pine, alder and beech were determined as 2.74 %, 3.71 % and 4.37 % of the deformation that occurred as a result of static shear test performed before creep test, respectively. Ultimately, the overall average creep deformation value of a single staple wood joint under creep loading was determined as 3.61 %., U radu su istraživana obilježja puzanja spojeva namještaja s klamericom izrađenih od borovine, johovine i bukovine pri različitim stupnjevima opterećenja. Stupnjevi opterećenja definirani su kao 30, 40 i 50 % najvećeg opterećenja dobivenoga kao rezultat statičkoga smičnog ispitivanja prije opterećenja pri puzanju te su primijenjeni na drvne spojeve napravljene klamericom. Rezultati laboratorijskih ispitivanja pokazali su da je najveća deformacija puzanja zabilježena na spojevima izrađenima od borovine, koja ima najmanju gustoću, a najmanja je deformacija puzanja uočena na spojevima od bukovine, koja ima najveću gustoću. Usto, najmanja deformacija puzanja spojeva zabilježena je pri stupnju opterećenja od 30 %, zatim se deformacija puzanja povećala pri stupnju opterećenja od 40 % i dosegnula najveću vrijednost pri stupnju opterećenja od 50 %. Rezultati ispitivanja puzanja pokazali su da je deformacija spojeva s klamericom izrađenih od borovine, johovine i bukovine iznosila 2,74, 3,71 i 4,37 % deformacije koja je rezultat statičkoga smičnog naprezanja provedenoga prije ispitivanja puzanja. U konačnici, ukupna prosječna vrijednost deformacije puzanja drvenog spoja s klamericom iznosila je 3,61 %.

The additive effects of the number of staples and gluing on ultimate lateral resistance loads of surface-to-surface, multistaple- and glue-connected joints in oriented strandboards (OSB) were investigated. Experimental results indicated that for a stapled–glued OSB joint with a given configuration of surface-tosurface bonding area of two joint members, its ultimate lateral resistance load and stiffness are governed by the number of staples used and gluing, respectively. Applying glue to multistaple-connected OSB joints can alter the effect of the number of staples used on their ultimate lateral resistance loads. Gluing increases joint lateral resistance loads, but this increase will not be significant when the number of staples used reaches a critical number. Applying glue to a stapled OSB joint improves its stiffness when compared with the stiffness of a stapled-only joint. The differences in ultimate lateral resistance loads of stapled–glued joints among three OSB materials evaluated in this study were not significant when the number of staples was six or less, and the differences became significant when the number of staples increased to eight.

This study was performed to evaluate effects of driving torques on direct screw withdrawal resistance (DSWR) in wood-based composites. Pilot hole diameters (1.6, 2, 2.4 mm), embedded screw orientations (edge-, end- and face-) and torque levels, that were obtained from the typical driving torque curve among two main driving torques, were selected to test on screw withdrawal resistance. The results of the study showed that the pilot hole diameters were needed to be chosen carefully related to the grain orientation. The screw withdrawal resistance in face-grain orientation had the highest DSWR than the ones in edge- and end- grain orientations. Based on the torque levels selected that the DSWR was lower at the torque level closer to the stripping torque levels in OSB.

Lateral shear resistance capacities of face-to-face single-staple and one-row vertically aligned multistaple joints in three oriented strandboards (OSB) were investigated and compared. Exp...

The aim of this study was to determine some technological properties of particleboard made from the waste from window joints. The effect of board density, adhesive amount, and paint presence on the properties of particleboard was investigated. Increasing density and adhesive amount significantly improved their mechanical properties and surface roughness, but negatively affected their thickness swelling. Removing of the paint from the particle resulted in better mechanical properties, but poorer (higher) surface roughness values. This treatment did not statistically affect the thickness swelling. Based on the results, it is proved that the waste of window joints has a potential as raw material for the manufacture of particleboard.

Particleboard is one of the most important wood-based panel products on the market. The objectives of this study are to investigate the relationship between the density profile and some technological properties of particleboard and to determine the influences of press type, cold and hot press pressures, moisture content of the raw materials on the mechanical properties (modulus of rupture, modulus of elasticity and internal bond strength), physical properties (thickness swelling and density profile), and surface property (surface roughness) of three-layered particleboard composite. Based on the findings of this study, it appears that there exists a relationship between the density profile and technological properties of particleboard. The press type, cold and hot press pressures and moisture content of the raw materials are significantly found to be effective on all of the properties of the panels.

In this study; the influences of moisture content of the particle before blending, paraffin usage and wood species on the physical (density profile, thickness swelling), mechanical (modulus of rupture, modulus of elasticity, internal bond strength) and surface quality (surface roughness) of particleboard were investigated. According to the test results; increasing moisture content of the surface layer particles improved the all of the properties of the panels. Particleboards consisting poplar particles in the surface layers had the highest quality values. Paraffin usage increased the surface smoothness.

In this study, properties of the coated boards, packaging, transportation, storage, cleaning on the boards and some points to be considered for the machining of the boards were investigated.

This study investigated some of the important physical (thickness swelling) and mechanical (modulus of rupture, modulus of elasticity and internal bond) properties of single-layer particleboard panels made from eucalyptus ( Eucalyptus camaldulensis Dehn.), waste of grass clippings ( Lolium perenne L.) and combinations of the two. The chemical properties (pH, holocelluse and alpha cellulose contents, and water, alcohol–benzene and 1% sodium hydroxide solubilities) of the raw materials were also determined. Panels with a 6:94 ratio of grass-to-eucalyptus particles had the required mechanical properties for interior fitments including furniture and general uses. Boards manufactured with 100% grass clippings exhibited the lowest quality. The overall panel properties improved with a lower percentage of grass clippings added. Based on initial results, it also appears that grass should compose no more than 13% to achieve acceptable panel properties for interior fitments and general uses.