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Öğe 3D-Printed Biocomposites from Hemp Fibers Reinforced Polylactic Acid: Thermal, Morphology, and Mechanical Performance(North Carolina State Univ Dept Wood & Paper Sci, 2025) Celik, Esra; Uysal, Mesut; Gumus, Omer Yunus; Tasdemir, CagatayThermal, morphological, and mechanical properties were studied for 3D- printed biocomposites prepared from polylactic acid (PLA) and hemp fibers. For this purpose, the neat PLA, PLA/Hemp fiber (3 wt%), PLA/Hemp fiber/Maleic anhydride (3 wt% and 0.6 wt%), and PLA/Hemp fiber/Maleic anhydride/Glycerol (3 wt% and 0.6 wt% + Glycerol added in 10% of PLA) biocomposites were extruded to obtain filaments for fused filament fabrication (FFF). Thermogravimetric analysis (TGA) provided temperatures corresponding to 5%, 10%, and 90% mass losses for materials before and after 3D printing. During 3D printing, filaments were extruded with a nozzle temperature of 220 degrees C; consequently, their thermal properties worsened after 3D printing. In thermal analysis, T g increased by adding hemp fiber and maleic anhydride but was decreased with glycerol addition. The tensile and flexural strengths of neat PLA and biocomposites were not statically different, but flexural strength was slightly increased by adding ingredients one by one. Regarding modulus of elasticity (MOE) of materials, the sample group of the PLA/hemp fiber/maleic anhydride had the highest value. However, glycerol addition decreased MOE by 17%. These results showed that material performance of the PLA could be improved or remain statistically identical by adding hemp fiber, maleic anhydride, and glycerol.Öğe Economic and Environmental Sustainability Performance Improvements in the Outdoor Wood Furniture Industry Through a Lean-Infused FMEA-Supported Fuzzy QFD Approach(Mdpi, 2025) Ince, Melike Nur; Arpaci, Emrecan; Tasdemir, Cagatay; Gazo, RadoFiercer competition across all industries has made identifying and eliminating lean wastes to enhance sustainability performance an effective route that many companies take. This study focuses on the production process of wood park/garden benches at a company that manufactures outdoor wood furniture. The goal was to identify lean wastes within a sustainability framework across seven operations and integrate multi-criteria decision making (MCDM) methodologies for waste elimination. Eleven lean KPIs addressing economic and environmental sustainability were used to develop and prioritize 13 lean failure modes (LFMs) with Risk Priority Numbers (RPNs) above 100, leading to lean project proposals for each LFM. Eighteen lean tools were ranked using the Fuzzy Quality Function Deployment (Fuzzy QFD) method. A total of eight improvement propositions, namely, Kaizen and continuous improvement, upgrade machinery for energy efficiency, Just-In-Time (JIT), optimize production processes with lean methodologies, implement cost reduction strategies, Total Productive Maintenance (TPM), Investing in Automation, and Andon were implemented. Significant improvements were observed post-implementation: total lead time was reduced by approximately 38.46%, value-added time by 22.05%, and non-value-added time by 47.64%. The required number of workers decreased by 14.29%, and the total inventory decreased by approximately 57.31%. The results contribute to sustainability goals by reducing energy consumption and waste while increasing economic efficiency. It also provides a robust framework for decision making in fuzzy environments, guiding practitioners and academics in lean management and sustainability.Öğe Effects of alkyl-ketene dimer on physical, mechanical and formaldehyde emission properties of particleboard produced with melamine-impregnated paper waste(Taylor & Francis Ltd, 2024) Basboga, Ibrahim Halil; Basboga, Hulya Varlibas; Tasdemir, Cagatay; Atar, Ilkay; Yuce, Ozcan; Karademir, Arif; Mengeloglu, FatihThis study aimed to enhance the physical properties and the weak heat transmission of the core layer, which are the weak points of particleboard produced using melamine-impregnated paper waste (MIPW) as an adhesive. Alkyl-ketene dimer (AKD) and paraffin were used as water-repellent chemicals. MIPW was used as an adhesive, and no additional resin was used. As a result of this study, the samples' physical properties improved with AKD and paraffin's existence. Moreover, it has been approved that AKD is more effective than paraffin in improving the physical properties of the particleboard because AKD improves ester bonding with hydroxyl groups of cellulose fibers. The usage of water repellents resulted in the improvement of internal bond (IB) properties. It was determined that the type and amount of water-repellent chemicals significantly affected the mechanical and physical properties and formaldehyde content of the produced particleboards, except for bending properties. Just the chemical type was found to be significantly effective on bending strength (BS) and modulus of elasticity (MOE) properties. Overall, the study findings suggested that AKD might be successfully utilized as a water-repellent chemical in particleboard manufacturing, while MIPWs used as an adhesive.Öğe Exploring and forecasting climate change and wood decay hazard trends in Türkiye(Springer Wien, 2025) Ari, Seren S.; Tasdemir, Cagatay; Tomak, Eylem D.Wood is an organic material, so it is susceptible to degradation by various biological agents. When temperatures range from 20 degrees C to 27 degrees C and humidity levels are between 65% and 70%, the conditions are ideal for fungal growth. In T & uuml;rkiye, wood materials typically used in outdoor environments fall within these ranges, making them vulnerable to fungal damage. Therefore, understanding climate index values is crucial for assessing the risk of fungal damage to outdoor wood materials in our country and for identifying the technical and practical measures needed to minimize the adverse effects of potential decay hazards. The study's objective is to classify the climate of provinces in T & uuml;rkiye and calculate climate index values using meteorological data from 2012 to 2023. In doing so, the study aims to link these values to the biological decay of wood. For this purpose, the Erinc climate classification and Scheffer Climate Index values were calculated using temperature and precipitation data over the last 11 years. These values were then categorized according to decay risk levels. Additionally, optimized SARIMA models were used to forecast climate classifications and index values over the next 5 years. As a result, the overall climate index for the periods 2012-2023 and 2024-2028 has decreased compared to previous years' values. The highest precipitation efficiency index was observed in the Eastern Black Sea region, while the lowest was found in the Southeastern Anatolia and Central Anatolia regions. On a provincial basis, the highest precipitation efficiency index was recorded in Rize, while the lowest was detected in Igdir. The values of the Scheffer Climate Index have increased slightly in recent years and are expected to continue rising. The highest Scheffer Climate Index values were observed in the Eastern Black Sea region, specifically in Rize, Giresun, Ordu, and Trabzon. In contrast, the lowest index values were found in Bitlis and Van in the Eastern Anatolia region, Karaman in the Central Anatolia region, and Batman in the Southeastern Anatolia region. The findings on climate indices indicate decreasing precipitation and increasing temperatures. In regions with a high risk of decay, it is essential to use impregnated wood for outdoor applications. As is the case globally, rising global temperatures in our country are causing significant changes in the climate and vegetation. As a result, wood used in outdoor environments is significantly impacted by seasonal factors, which can alter its service life over time. Particularly in recent years, decreases in precipitation and corresponding increases in temperature and global solar radiation are likely to change the factors that cause wood damage. Given the expected rise in fungal attacks, insect and termite infestations, and photodegradation in the coming years, it is necessary to promote the use of impregnated or modified wood products for outdoor applications and raise public awareness about these issues.Öğe Facility layout planning through the ALDEP Method in the wooden cable reels industry(2024) İnce, Melike Nur; Tasdemir, CagatayFacility layout planning plays a pivotal role in manufacturing system design, impacting vital metrics such as lead time, handling costs, and space optimization. While a significant portion of research has been invested in refining existing facility layouts, there is a noticeable research gap in devising optimized layouts for new establishments, especially in the value-added wood products domain. Addressing this lacuna, this research focused on designing an efficient department-level layout for a wooden cable drums manufacturing facility in an area of 4150 m2. This facility included both office and production areas. The investigative process was segmented into four distinct phases: Deciding the strategic positioning of the facility on the available plot, defining the functional and spatial requirements for each department, establishing the intricate relationship dynamics between these individual units, and rigorously documenting the most optimal department-level facility layout. For precision in layout creation, the ALDEP algorithm was employed, which was further visualized to offer a comprehensive three-dimensional representation. The final layout seamlessly organized seven departments within the 1st Floor Office Area, eight in the 2nd Floor Office Area, and thirteen within the Production Floor. Efficiency evaluation of these areas yielded scores of -811, 184, and -318, respectively. Conclusively, this research furnished actionable insights for manufacturers within the wood products sector and was expected to be an invaluable reference for academics delving into facility planning and value-added wood products manufacturing.Öğe Facility Location Selection and Layout Planning through AHP, PROMETHEE, and CORELAP Methods in the Furniture Industry(North Carolina State Univ Dept Wood & Paper Sci, 2024) Ince, Melike Nur; Tasdemir, CagatayFacility location selection and internal layout planning are critical strategic decisions for long-term sustainability. This study identified the most feasible location and optimal layout for a commercial bedroom furniture manufacturing facility through a seven-phase evaluation of Istanbul, Ankara, Izmir, and Bursa. The Analytical Hierarchy Process (AHP) and PROMETHEE were used for city and district selection, with AHP calculating criteria weights and PROMETHEE ranking alternatives. The Borda Count Method aggregated MCDM results, selecting Istanbul as the optimal city and Dudullu Organized Industrial Zone (O.I.Z.) as the most favorable district. The CORELAP method developed an optimal single- story layout for a 2688 m2 2 production and assembly facility, enhancing production flow, reducing material handling costs, and improving efficiency. These findings underscore the importance of strategic facility location and layout planning in improving the furniture industry's competitiveness and sustainability. The practical implications of this research are significant, as the findings can be directly applied to improve the competitiveness of the furniture industry. The study offers a comprehensive framework for strategic decision-making, providing valuable insights and a systematic approach applicable to similar problems in various sectors.Öğe Forecasting Retail Sales for Furniture and Furnishing Items through the Employment of Multiple Linear Regression and Holt-Winters Models(Mdpi, 2024) Ince, Melike Nur; Tasdemir, CagatayGlobal economic growth, marked by rising GDP and population, has spurred demand for essential goods including furniture. This study presents a comprehensive demand forecasting analysis for retail furniture sales in the U.S. for the next 36 months using Multiple Linear Regression (MLR) and Holt-Winters methods. Leveraging retail sales data from 2019 to 2023, alongside key influencing factors such as furniture imports, consumer sentiment, and housing starts, we developed two predictive models. The results indicated that retail furniture sales exhibited strong seasonality and a positive trend, with the lowest forecasted demand in April 2024 (USD 9118 million) and the highest in December 2026 (USD 13,577 million). The average annual demand for 2024, 2025, and 2026 is projected at USD 12,122.5 million, USD 12,522.67 million, and USD 12,922.17 million, respectively, based on MLR, while Holt-Winters results are slightly more conservative. The models were compared using the Mean Absolute Percentage Error (MAPE) metric, with the MLR model yielding a MAPE of 3.47% and the Holt-Winters model achieving a MAPE of 4.21%. The study's findings align with global market projections and highlight the growing demand trajectory in the U.S. furniture industry, providing valuable insights for strategic decision-making and operations management.Öğe Investigation of Indoor Noise Pollution Level and Air Quality of Furniture Manufacturers(North Carolina State Univ Dept Wood & Paper Sci, 2024) Tasdemir, Cagatay; Yildirim, Yalcin; Uysal, Mesut; Angin, Naile; Ertas, MuratIndoor air quality has become a more prominent concern since the arrival of the COVID-19 pandemic. Manufacturing industries have always been prone to occupational health risks, which depend on the dynamics of the production shop floors. The furniture industry is one of these sectors with a unique work environment. Although a typical furniture manufacturing facility involves physical, chemical, and noise pollution-producing elements, this industry has been studied relatively less for indoor air quality and noise-related risks. This study investigated nine fumiture manufacturing organizations' indoor air quality and noise pollution levels through comprehensive quantitative techniques. The results of the measurements were compared against reference values set by specific guidelines to explore the degree of occupational health risk associated with the World Health Organization's (WHO) suggested levels. Repetitive measurements from five pre-designated workstations were taken at each facility. The study's results indicated that organization size and department were significant factors for PM 2.5 and HCHO parameters, while only department type was substantial for noise exposure levels. However, across all departments and organization sizes, LAeq noise levels were below the safety threshold of 85 dB(A). Most organizations presented a lack of proper use of personal protective equipment and poor ventilation across shop floors.Öğe The Impact of Quality Dimensions and Some Other Critical Factors on Consumers’ Furniture Purchasing Decisions(2024) İnce, Melike Nur; Tasdemir, CagatayThis research examined the influence of quality dimensions and various other factors on consumer choices in the Turkish furniture market, aiming to bridge a literature gap by leveraging theoretical insights and empirical data. Utilizing a detailed survey, the study captured consumer perceptions of factors influencing furniture purchases, focusing on Garvin's eight quality dimensions: Suitability, Perceived Quality, Features, Aesthetics, Service, Durability, Reliability, and Performance. The methodology included a 19-question survey targeting Bursa's population to gather data on demographic characteristics and purchasing influences, which was analyzed via Microsoft Excel. The findings underscored the paramount importance that consumers placed on durability and performance, suggesting a pragmatic approach to furniture buying where functionality trumped aesthetics. A notable preference for sustainable and eco-friendly furniture emerged, aligning with broader environmental trends. Demographically, most respondents were young, university-educated adults, indicating a market segment with distinct tastes and preferences, particularly toward modern-style furniture. These insights advocated for furniture industry stakeholders to adopt marketing strategies emphasizing product durability, performance, and environmental friendliness, aligning with consumer expectations for quality and sustainability. This alignment could be crucial for guiding product development and design to cater to contemporary consumer needs.
