Odunun işlenmesinde yüzey pürüzlülüğü üzerine etkili faktörler

Mobilya ve dekorasyon endüstrisinde kullanılan ahşap ürünlerin yüzey pürüzlülüğünün ölçülmesi son ürünün kalitesinin tespit edilmesi bakımından oldukça önemlidir. Yüzey pürüzlülüğü odun ürünlerin estetikliğini ve pazarlanma aşamasında müşteri talebini önemli ölçüde etkilemektedir. Bununla beraber, odunun yüzey pürüzlülüğünün odun yüzey işlemlerinin uygulanmasında adezyon direnci üzerine önemli bir etkiye sahip olduğu için tespit edilmesi gerekir. Ancak, yüzey pürüzlülüğünün belirlenmesi üzerine ilk çalışmalar metal endüstrisi üzerine yoğunlaşmıştır. Odunun yüzey pürüzlülüğünün belirlenmesi konusundaki çalışmalar ise 20. yüzyılın ortalarına dayanmaktadır. Bu amaçla çeşitli pürüzlülük ölçüm yöntemleri geliştirilmiştir. Bu araştırmada, odun yüzey pürüzlülüğünün önemi, yüzey pürüzlülüğü üzerine etkili olan faktörler, yüzey pürüzlülüğü ölçüm yöntemleri ve yüzey pürüzlülüğünün belirlenmesinde kullanılan parametreler araştırıldı. Anahtar kelimeler: Yüzey pürüzlülüğü, Pürüzlülük ölçüm yöntemleri, Odunun işlenmes

TÜRKİYE MOBİLYA SEKTÖRÜNÜN AVRUPA BİRLİĞİ SÜRECİNDE DIŞ TİCARET DURUMUNUN KÜMELEME ANALİZİ İLE İNCELENMESİ

Türkiye mobilya sektörü son yıllarda hızlı bir büyüme göstermektedir. Sektörün 2023 yılı için öngörülen hedefiDünya’da ilk 10, Avrupa da ise ilk 5 de yer almaktır. Bu bakımdan mobilya sektörünün dış ticaret durumunun analizi önemlidir. Bu çalışmada, Türkiye mobilya sektörünün Avrupa Birliği üyeleri içindeki durumunun belirlenmesi amaçlanmıştır. Avrupa Birliği üyesi 28 ülke ve Türkiye’nin 2004-2013 yılları arasındaki 10 yıllık süreç için mobilya ithalat ve ihracat değerleri aşamalı kümeleme analizine tabi tutulmuştur.Sonuç olarak, ihracat ve ithalat hacmi bakımından Türkiye’nin orta sıralarda yer aldığı belirlenmiştir. Almanya ve İtalya ihracat bakımından en yüksek değere sahip olup aynı grupta yer alırken en yüksek ithalat değeri ile Almanya tek başına bir grupta yer almıştır

Utjecaj ocjene rada na motivaciju i produktivnost zaposlenika u turskoj industriji proizvoda na bazi šuma: analiza strukturnih jednadžbi modela

The present study investigates the influence of performance appraisal on employee motivation and productivity in Turkish forest products industry using a structural equation model. The questionnaires prepared for this purpose were applied to 432 people that work in 14 forest products industry businesses operating throughout Turkey. A total of nine hypotheses were established to determine the relationship between performance appraisal and employee motivation and productivity. The results indicated that five hypotheses were accepted, while four of them were rejected. In the light of the findings of this study, it may be generally said that the effect of performance appraisal on employee motivation and productivity was high. In other words, performance appraisal was found to be a major factor on employee motivation and productivity. The present study is expected to help managers and decision makers in selecting suitable motivating factors in order to retain and satisfy their employees. Consequently, this study will fill an important gap in the area of performance appraisal in the forest products industry by structural equation modeling and presents the opportunity for further studies.Studija je prikaz istraživanja utjecaja ocjene rada na motivaciju i produktivnost zaposlenika u turskoj industriji proizvoda na bazi šuma primjenom modela strukturnih jednadžbi. Na upitnike pripremljene za tu namjenu odgovarale su 432 osobe zaposlene u 14 tvrtki u sektoru industrije na bazi šuma diljem Turske. Pritom je postavljeno devet hipoteza za utvrđivanje odnosa ocjene rada i motiviranosti i produktivnosti zaposlenika. Rezultati su pokazali da je pet hipoteza prihvatljivo, a četiri su odbijene. U svjetlu nalaza ove studije može se reći da je učinak ocjenjivanja na motiviranost zaposlenika i produktivnost vrlo visok. Drugim riječima, ocjena rada najviše utječe na motiviranost zaposlenika i na njihovu produktivnost. Očekuje se da će rezultati studije pomoći menadžerima i donositeljima odluka u odabiru odgovarajućih motivacijskih čimbenika kako bi zadržali i zadovoljili svoje zaposlenike. Stoga će ova studija ispuniti jaz koji postoji u području ocjenjivanja rada u drvnoj industriji modeliranjem strukturnih jednadžbi te će otvoriti mogućnosti daljnjeg istraživanja

Análisis comparativo del impacto, de la segregación de los datos por género, en los protocolos de investigación de fisiología reproductiva y cardio-respiratoria

Es un hecho conocido que el dimorfismo sexual se presenta en la mayoría de las especies animales. Las diferencias que esto conlleva, tienen una base genética que sustenta características físicas propias de machos o hembras. Conocido esto, es evidente la necesidad de determinar la incidencia genérica en el funcionamiento de cualquier organismo. Sin embargo, el presente análisis, ha permitido comprobar que, la inclusión en la segregación de los resultados por género en estudios de Bio-Medicina (clínicos y pre-clínicos) aún no es algo generalizado. Para ello, se han revisado y combinado los resultados de un conjunto de estudios (fechados entre 2011 y 2017) escogiéndose dos áreas (en cuyas fisio-patologías se acepte diferente grado de impacto del género): aparato reproductivo y el sistema cardio-respiratorio. Los resultados obtenidos confirman la necesidad de concienciar a la comunidad científica de la importancia de la inclusión de la variable “género” en este tipo de estudios.It is a known fact that sexual dimorphism occurs in most animal species. The differences that this entails have a genetic basis that supports physical characteristics of males or females. Once this is known, the need to determine the generic incidence in the functioning of any organism is evident. However, the present analysis has shown that inclusion in the segregation of results by gender in Bio-Medicine studies (clinical and pre-clinical) is not yet widespread. For that, the results of a series of studies (dated between 2011 and 2017) have been reviewed and combined, choosing two areas (in whose physio-pathologies a different degree of gender impact is accepted): reproductive system and the cardio-respiratory system. The results obtained confirm the need to make the scientific community aware of the importance of including the gender variable in this type of studies

The influence of raw material growth region, anatomical structure and chemical composition of wood on the quality properties of particleboards

In the present study, the impact of raw material grown region on the physical, mechanical, surface properties and formaldehyde emission of the particleboard was investigated. Ailanthus altissima wood grown in Trabzon had longer fiber length and thicker fiber and trachea cell wall than those of the wood grown in Artvin. The highest amounts of lignin, ash, condensed tannin and solubility values were found in wood grown in Artvin. Ailanthus altissima wood grown in Trabzon had higher amounts of cellulose and hemicellulose than those of the wood grown in Artvin. Particleboards made from wood grown in Artvin had worse surface quality and mechanical strength properties than those of panels made from wood grown in Trabzon. On the other hand, the results showed that particleboards produced from wood grown in Artvin had lower thickness swelling and formaldehyde emision values than those of the panels produced from wood grown in Trabzon

Application of artificial neural networks for predicting tensile index and brightness in bleaching pulp

The purpose of this study was to develop artificial neural network (ANN) models for predicting the effects of wood species, sodium perborate tetrahydrate (SPBTH) ratio, time, and beating degree on tensile index andbrightness in bleaching pulp. Unbleached kraft-AQ bamboo and poplar pulps were exposed to first stage oxygen delignification for bleaching under 0,5 MPa, 3% NaOH and 12% consistency conditions. SPBTH bleaching was then carried out as the final stage. SPBTH bleached pulp was next beaten using two different degrees (55 SR° and 65 SR°). Tensile index and brightness data for training, validation and testing of the models were elicited from these experimental investigations. The models were established using the resulting data. The lowest R2 value was 0,98 among training, testing and validation data sets in the prediction of both tensile index and brightness. The networks therefore explain at least 98% of the experimental data for all data sets. The results indicate that ANN is a useful and effective tool for predicting tensile index and brightness. Thisstudy thus describes a novel and alternative approach to predicting tensile index and brightness in bleaching pulp compared to the literature

Multivarijatni kontrolni dijagram Hotelling T2 za praćenje nekih svojstava kvalitete u proizvodnji ploča vlaknatica srednje gustoće

Statistical process control tools are of great importance in terms of controlling manufacturing processes and improving product quality. In this study, the manufacturing process of medium density fiberboards manufactured in a company operating in the forest products industry was monitored by using multivariate Hotelling T2 statistical process control chart in terms of some quality characteristics. The T2 values of the signals detected by the Hotelling T2 control chart were also decomposed. By the decomposition of T2 values, it was determined which quality characteristics contributed more to each signal. It was seen that the process was not in control for Hotelling T2 control chart, which reveals the shift level in the mean of quality characteristics. As a result, the application of Hotelling T2 allowed fast detection of possible abnormalities in the process. The decomposition of T2 values successfully revealed which quality characteristics contributed significantly to the signals. Besides, it was concluded that, for monitoring, the Hotelling T2 chart was able to employ simultaneously different quality characteristics of medium density fiberboard. The current application study also contributed to the emergence of the root causes of the large shifts in the process. In conclusion, the findings of the study enabled the company to ensure the process stability and to facilitate decision-making on actions to be taken for quality improvement.Statistički alati za praćenje procesa vrlo su važni za kontrolu proizvodnih procesa i poboljšanje kvalitete proizvoda. U ovom su istraživanju praćena neka obilježja kvalitete procesa proizvodnje ploča vlaknatica srednje gustoće primjenom multivarijatnoga kontrolnog dijagrama Hotelling T2. Napravljena je dekompozicija T2 vrijednosti signala detektiranih kontrolnim dijagramom Hotelling T2. Dekompozicijom T2 vrijednosti utvrđeno je koja obilježja kvalitete više pridonose pojedinom signalu. Iz kontrolnog dijagrama Hotelling T2 vidjelo se da proces nije pod kontrolom, što dovodi do pomaka srednjih vrijednosti karakteristika kvalitete. Kao rezultat toga, primjena kontrolnog dijagrama Hotelling T2 omogućila je brzo otkrivanje eventualnih abnormalnosti u procesu proizvodnje. Dekompozicijom vrijednosti T2 uspješno je otkriveno koja su svojstva kvalitete značajno pridonijela signalima. Osim toga, zaključeno je da se kontrolni dijagram Hotelling T2 može primijeniti za istodobno praćenje različitih obilježja kvalitete ploča vlaknatica srednje gustoće. Trenutačna primjena studije također je pridonijela otkrivanju temeljnih uzroka velikih pomaka u procesu. Zaključno, nalazi studije omogućili su promatranoj tvrtki da stabilizira proces proizvodnje i olakša donošenje odluka o postupcima za poboljšanje kvalitete ploča vlaknatica

The influence of raw material growth region, anatomical structure and chemical composition of wood on the quality properties of particleboards

In the present study, the impact of raw material grown region on the physical, mechanical, surface properties and formaldehyde emission of the particleboard was investigated. Ailanthus altissima wood grown in Trabzon had longer fiber length and thicker fiber and trachea cell wall than those of the wood grown in Artvin. The highest amounts of lignin, ash, condensed tannin and solubility values were found in wood grown in Artvin. Ailanthus altissima wood grown in Trabzon had higher amounts of cellulose and hemicellulose than those of the wood grown in Artvin. Particleboards made from wood grown in Artvin had worse surface quality and mechanical strength properties than those of panels made from wood grown in Trabzon. On the other hand, the results showed that particleboards produced from wood grown in Artvin had lower thickness swelling and formaldehyde emision values than those of the panels produced from wood grown in Trabzon

Consumer preferences for flooring in Turkey in terms of purchasing and use

In this study, consumer preferences for flooring in terms of purchasing and use, were investigated, as well as consumer attitudes and the reasons for preferences for a particular product, and whether consumer behaviour varied according to gender; age, level of education, occupation and size of household. The study was based on a face-to-face interview of 1005 people throughout Turkey. The data obtained from the survey was analyzed using the statistical package SPSS 19.0 for Windows. According to the results of the study, it is possible to say that the customers preferred flooring which was easy to assemble, with good heat and sound insulation, resistant to physical and mechanical damage, both environmentally- and human-friendlyand aesthetically pleasing. Manufacturers should therefore endeavour to meet these expectations by obtaining positive and negative feedback from users of flooring. In conclusion, it was determined that flooring preference, usage, expectations and consumer complaints may differ according to gender, age, level of education, income level, household size and occupation. This study fills an important gap regarding the investigation of consumer preferences for flooring in terms of purchasing and use in Turkey