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International Symposium for Production Research, ISPR 2023
No full textThis paper presents a proposal for an Excel-based digital inventory tracking system to address the operational challenges faced by a leather label manufacturer located in Istanbul, Turkey. The company is currently reliant on manual stock keeping and tracking methods for its leather labels and raw materials, resulting in significant functional difficulties due to the absence of a systematic and efficient inventory tracking system. The proposed system aims to enhance overall productivity and decision-making processes within the company. By implementing the new tracking system, the company can overcome the limitations of manual stock management, leading to improved efficiency and organization in inventory control. Furthermore, the installation of a barcode system is suggested to augment the tracking system’s capabilities, and the profitability of the proposed system is evaluated using three different financial analysis methods. This research contributes to the advancement of inventory management practices and provides valuable insights into the potential benefits of adopting digital solutions for stock control in the leather label industry. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024
Insights Into Early Childhood English Education: A Comparative Analysis of Perspectives Between English Teachers and Preschool Teachers
No full textThe study aims to illuminate and compare of the perceptions of Turkish preschool and EFL teachers regarding English language education in the preschool years. The study is a basic qualitative research method involving 16 Turkish EFL and Turkish preschool teachers. As a result, the teachers showed similar views about early English education benefits a child’s language, cognitive, and socio-emotional development. However, both groups expressed dissatisfaction with the quality of early English education, highlighting the challenges. Teachers emphasized that English language should be taught by native Turkish speakers rather than native English speakers. © 2024 ASPE
The Immediate Effect of Hanging Exercise and Muscle Cylinder Exercise on the Angle of Trunk Rotation in Adolescent Idiopathic Scoliosis
No full text(1) Background: Semi-hanging and muscle cylinder exercises have been defined as scoliosis-specific corrective exercises. The aim of this study was to evaluate the immediate effect of muscle cylinder and semi-hanging exercises on the angle of trunk rotation in patients with adolescent idiopathic scoliosis (AIS). (2) Methods: Twenty-seven patients with AIS with a mean age of 18.6 years were retrospectively analyzed. The angle of trunk rotation (ATR) values were measured before and after performing semi-hanging and standing muscle cylinder exercises. Both exercises were performed for three to five respiratory cycles. The semi-hanging exercise was performed first, followed by the muscle cylinder exercise, in this order, in all participants. For statistical analysis, the Wilcoxon signed-rank test was used to analyze ATR changes after the exercises, and the Kruskal-Wallis test was used to compare ATR changes according to the main curve location. (3) Results: The thoracic, thoracolumbar and lumbar maximum ATR values were significantly increased after the semi-hanging exercise (p < 0.001) and decreased after the muscle cylinder exercise (p < 0.001). The ATR change was greater in the lumbar region than in the thoracic and thoracolumbar regions. (4) Conclusion: The results of this study of a small group of patients emphasized that one of the scoliosis-specific corrective exercises, the standing muscle cylinder exercise, improved ATR, while the other, the semi-hanging exercise, worsened ATR in patients with AIS. It is recommended that each scoliosis-specific corrective exercise be evaluated and redesigned to maximize the three-dimensional corrective effect, considering the biomechanics of the spine and the pathomechanics of scoliosis
On the Harary Index of Γ(Zn)
No full textIn this work, the Harary index of zero-divisor graphs of rings Zn are calculated when n is a member of the set {2p, p2, pλ, pq, p2 q, pqr} where p, q and r are distinct prime numbers and λ is an integer number. We give the formulas for computing the Harary index of Γ(Zn). Moreover, the Harary index of graphs for products of rings were computed. © 2024, Bayram Sahin. All rights reserved
Revisiting Structural, Vibrational, and Photochemical Data of Matrix-Isolated Simple Hydantoins — Common Features and Substituent Effects
No full textCharacteristic features of the structure (geometries, electronic structures), vibrational spectra (infrared), and photochemistry of a series of simple hydantoins (parent hydantoin, 1-methylhydantoin, 5-methylhydantoin, and 5-acetic acid hydantoin), and effects of substituent on these properties, are reviewed in a comparative comprehensive perspective taken as a basis the low-temperature matrix isolation infrared spectroscopy and electronic structure quantum chemistry data we have reported before for the individual compounds. It is shown that the hydantoin moiety shows a general tendency towards planarity (or quasi-planarity), mostly determined by the π-electron delocalization in the system, in which the two nitrogen atoms are extensively involved and, in the molecules studied, also counts with the involvement of the π-type orbitals of the -C5H2- or -C5HR- (with R ˭ CH3 or CH2COOH in 5-methylhydantoin and 5-acetic acid hydantoin, respectively) fragment (hyperconjugation). The geometries and charge density analyses of the compounds also show that the main electronic effects in the hydantoin ring are the N-to-(C ˭ O) π-electron donation, and the σ system back-donation from the σ-lone electron pairs of the oxygen atoms to the ring. The frequencies of the bands observed in the matrix-isolation infrared spectra (Ar; 10 K) of the different compounds that are assigned to the carbonyl and amine fragments are discussed comparatively, and substituent effects are assessed. Finally, the UV-induced (λ = 320 nm) photochemistry of the hydantoins is shown to share a common pattern, leading to the concerted extrusion of isocyanic acid and carbon monoxide, accompanied by an imine derivative that depends upon the specific hydantoin reactant. An additional photofragmentation pathway, most probably involving nitrene intermediacy, also takes place for 1-methylhydantoin, indicating a specific effect of the substitution at position 1 of the hydantoin ring on the photofragmentation of hydantoins. © 2024 Author(s).Fundacao para a Ciencia e a Tecnologia (FCT)
A Study on the Determination of Trust, Satisfaction and Expectation Levels of University Students
No full textBu çalışma, üniversite öğrencilerinin güven, memnuniyet ve beklenti düzeylerini ölçmeyi ve bu değişkenler arasındaki ilişkileri ortaya çıkarmayı amaçlamaktadır. Alanyazında kişilerin güven ve memnuniyet düzeylerinin bir kurum veya kuruluş ile sürdürülen ilişkiyi etkilediği görülmektedir. Ayrıca, beklenti ile güven ve memnuniyet arasında anlamlı bir ilişki bulunmaktadır. Bu doğrultuda, çalışmanın temel motivasyonu, üniversite öğrencilerinin okullarına ilişkin güven, beklenti ve memnuniyet algılarını ölçmek ve bu değişkenler arasındaki ilişkilerin ortaya çıkarılmasıdır. Bu sayede üniversite öğrencilerinin okullarına karşı tutum ve beklentilerinin ortaya çıkartılması amaçlanmaktadır. Araştırmanın örneklemini Türkiye’deki üniversitelerde eğitim gören lisans öğrencileri oluşturmaktadır. Bu doğrultuda, 2021-2022 eğitim öğretim döneminde 136 üniversite öğrencisine anket yoluyla ulaşılmıştır. Araştırmanın amacı doğrultusunda, tanımlayıcı istatistiki analizler, faktör analizi, geçerlik ve güvenirlik analizleri ve korelasyon analizi uygulanmıştır. Ayrıca memnuniyet değişkenin yordayıcılarının belirlenmesi için çoklu doğrusal regresyon analizi, sosyodemografik değişkenler açısından değişkenlerin ne ölçüde farklılaştığını anlamak üzere bağımsız örneklem t-testi uygulanmıştır. Elde edilen sonuçlar neticesinde öğrencilerin üniversitelerine duydukları güvenin, memnuniyet düzeylerini önemli ölçüde yordadığı görülürken, beklenti düzeylerinin herhangi bir yordayıcı etkisinin olmadığı sonucuna ulaşılmıştır. Ayrıca, gelişim beklentisi ve kişisel gelişimden memnuniyet açısından cinsiyetler arasında anlamlı bir fark olduğu bulunmuştur. Bu doğrultuda, kadınların gelişim beklentisi ve kişisel gelişimden memnuniyet düzeylerinin erkeklere göre daha yüksek olduğu görülmektedir. Araştırma sonuçlarında, akademisyen ve uygulayıcılar için öneriler sunulmuştur
International Symposium for Production Research, ISPR 2023
No full textQuality controls are activities to evaluate the level of conformity of product attributes and optimal quality objectives. When 100% inspection is applied in quality control processes, sampling is used because it causes high costs, long control times and product damage. Acceptance sampling, which is a statistical method, determines whether the lot can be accepted or rejected in line with the tests performed on the samples taken from the lot. The acceptance sampling plan depends on multiple factors such as the level used, the degree of control applied, the lot size, and the acceptable quality level. For this reason, the use of standard sampling plans that increase the validity of quality control operations can be expressed. In this paper, acceptance process applications were studied for a the company that demonstrates textile industry studies. In this the company, the control processes entered the products in the batch of different sizes coming from the regulations used for the contract are applied. To determine the acceptance listening, the execution of the lot, the control measurement dimensions entered first, the reasons for the return of the the company’s four product groups and the AQL reports are reviewed, and the statistical evaluations of the quality controls come to an end. Next steps, using ANSI/ASQ Z-1.4, observations suitable for lot sizes and appropriate acceptance-rejection details were determined and compared with the size and decision points of the the company. Cause-effect diagrams do not take into account the reasons that cause the returns to be made so that the possible reasons for the returns can be examined. Finally, according to the results of the sampling, solutions were found to make the dimensions for these reasons. Cause-effect diagrams do not take into account the reasons that cause the returns, so that possible causes of the returns can be examined. Finally, according to the sampling results, solutions were found for sizing for these reasons. It is recommended to taken 50 samples from lot sizes between 281–500, 80 samples from 501–1200 lot sizes, and 125 samples for lot sizes between 1201 and 3200. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024
Unveiling the Red and Brownish-Green Polymorphs of a Novel ROY Derivative: 2-(4-((3-Cyanothiophen-2-yl)amino)-3-nitrophenyl)Acetic Acid
No full textPolymorphism has been the subject of many studies in the last decades, including a particular type of polymorphism where the colors exhibited by the polymorphs differ. However, only relatively limited or narrow differences in color were observed in color polymorphs of the same compound. Indeed, to this date, almost all compounds known to show color polymorphism exhibit red, orange, or yellow tones, as is the case of the notable ROY molecule (5-methyl-2-[(2-nitrophenyl)-amino]-3-thiophenecarbonitrile), which is the compound with more polymorphs reported and structurally characterized hitherto. In this work, we report a new color polymorphic material derived from ROY, (2-(4-((3-cyanothiophen-2-yl)-amino)-3-nitrophenyl)-acetic acid; or ROY-CAM), synthesized for the first time by nucleophilic aromatic substitution reaction between 2-(4-fluoro-3-nitrophenyl)-acetic acid and 2-aminothiophene-3-carbonitrile, which exhibits a red (P21/n, m.p.: 184 C-degrees and theta = -4.4(degrees) and 3.0(degrees)) and a brownish-green polymorph (P1, m.p.: 190 C-degrees and theta = -66.1(degrees)). This is the first time a member of the ROY family of compounds was observed to exhibit a brownish-green polymorph and, more importantly, the first time that a molecular compound exhibits a red and a greenish polymorphs, i.e., this is the first example of an organic molecule that originates polymorphs covering such a wide range of color. The isolated molecule of ROY-CAM has 11 low-energy conformers, which were accessed by DFT calculations, with two of these conformers being identified in the observed polymorphs of the compound: in the brownish-green polymorph, the most stable conformer exists, while the red polymorph is composed of molecules assuming a conformation similar to that of the third most stable conformer. In the latter polymorph, the intramolecularly disfavored conformation assumed by the molecules is stabilized in the crystal lattice through interactions between carboxylic acid groups of neighboring molecules, resulting in dimeric units formed between pairs of the two distinct molecules that constitute the asymmetric unit of the crystal. The two identified polymorphs were characterized vibrationally (by both IR and Raman spectroscopies), and a thermal study is also presented (based on DSC, PLTM, and TGA measurements). Furthermore, the brownish-green and red colors exhibited by the polymorphs of ROY-CAM are explained based on the differences in the structures of the molecules that are present in these crystals.Fundacao para a Ciencia e a Tecnologia (FCT