SACM - South Korea
Permanent URI for this collectionhttps://drepo.sdl.edu.sa/handle/20.500.14154/9665
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Item Restricted The practical application of 3D printers in the fabrication of a flexible heatsink for heat applications(Keimyung University, 2024-02-15) Alshammari, Talal; Kim, JonghyunThe innovative concept of converting solid thermal reducers into flexible counterparts has emerged as a captivating advancement in the realms of thermal management and material science. Flexible designs represent a dynamic and adaptable solution in the domain of thermal management. This study endeavors to concentrate on the meticulous design and manufacturing of high-performance heatsinks by using 3D printing with exceptional flexibility, specially tailored for effortless integration into collapsible electronic devices. The fabrication of heatsinks with varying ratios of Multi-Walled Carbon Nanotube (MWCNT) and Polydimethylsiloxane (PDMS) was conducted, and the optimal ratio was determined based on design elements (i.e., fin length, fin design, heat dissipation efficiency, tensile strength, flexibility, and bending moment analysis). The heatsink with 5% MWCNTs in PDMS displayed the optimal highest efficiency in heat dispersion. Bending and tension tests approved the excellent mechanical properties of the flexible heatsink. The effectiveness of the flexible heatsink based on MWCNT/PDMS has been proven experimentally to be wearable. These results reveal that the MWCNT/PDMS composite-based heatsink can be a good candidate in the thermal interface for the thermal management of electronic devices.17 0Item Restricted The Impact of Push and Pull Factors and Attitudes Towards Religion on Korean Travelers Intention to Visit Saudi Arabia(Saudi Digital Library, 2023-12-26) Alkurashi, Bashaer Salem; Nam, YoonjaeThe Korean travel market is one of the most important international markets for many countries around the world. Millions of Koreans travel abroad each year either for business, leisure, or holiday. However, many Saudi researchers are yet to shine the light and further investigate this. In order to increase the number of Korean travelers who are visiting Saudi Arabia, it is important to learn and understand what are the push and pull factors that will influence their travel-related intention for developing appropriate marketing strategies to attract them. Also, to find out if their attitudes towards religion had an impact on their travel intention to visit Saudi Arabia, is it a positive impact or a negative impact? This study was aiming to examine travel intention of Korean travelers to Saudi Arabia by using the push and pull motivational factor. The main objective of this research paper was to determine the impact of push and pull factors on travel intentions among Korean travelers. Next, the research paper analyzed how did push and pull factors impacted Korean travelers Intention to visit Saudi Arabia and how did the effect of attitudes towards religion motivated travelers and transformed their motivation into action (travel intention). To test the hypotheses and relationship between the variables, the survey data was analyzed through a factor analysis, reliability test, correlation test, as well as hierarchical multi-regression. A total of 254 valid Korean participants in and outside of Korea took part in the questionnaire survey, for which a snowball sampling technique was used. From the results, it was found that there was a significant relationship between push factors and Korean travel intention. It was also found that there was a significant relationship between their attitudes towards religion and their travel intention. The results of this study help to provide insight into which push and pull factors the Saudi Arabia tourism and marketing industry should focus on to better reach, attract, and stimulate the travel intentions of Korean tourists to Saudi Arabia.116 0Item Restricted Optimization and Characterization of Phoenix dactylifera L. Extracts on Anti-oxidant, Anti-melanogenesis, and Anti-diabetic Potentials(Saudi Digital Library, 2023-11-15) Alshammari, Fanar Hamad; Sang-Han, LeeThe optimization of the extraction of various dates from Tunisia, Algeria, Egypt, and other locations and their polyphenolic content as well as antioxidant activities were described in the prior literature; however, no systematic statistical technique was applied [1,18,19]. Additionally, the majority of the optimization of the extraction process was performed solely using RSM methodology, but the illustrious scientists made no attempt to compare the efficacy of predictive modeling with alternative, more effective methods such as ANN. Furthermore, to the best of our knowledge, this is the first study to use heat extraction (HE) with RSM and ANN to enhance the polyphenolic components and antioxidant activity of ripe Ajwa Date Seed (ADS) extracts. The aim was to use the RSM Box Behnken Design (BBD) tool to investigate and optimize extraction parameters such as extraction temperature, time, and ethanol concentration to acquire the maximum polyphenolic content and antioxidant potentiality from ADS. We argue that the projected values generated by the RSM-BBD approach correspond to the actual results and that this statistical tool is an effective model to optimize ADS polyphenolic compound extraction and antioxidant activity. The estimating capabilities and modeling effectiveness of the RSM and ANN models were also statistically examined. Additionally, we have also profiled the secondary metabolites of ADS using high-resolution mass spectrometry analysis. About 15% of world population accounts for consuming whitening agents of skin in Asia along with increased interest about inner beauty products of skin whitening. Human skin, hair, and iris color are all determined by melanin, which is biosynthesized by three enzymes in human (74,80). Accumulation of melanin is dysregulated by melanogenesis process within the intracellular melanosomes presented in melanocytes [80]. Tyrosinase is a multifunctional enzyme taken part in production of melanin, which catalyzes the hydroxylation and subsequent oxidation of tyrosine, making it a crucial and rate-limiting processes of melanogenesis. It has been reported that tyrosinase-related protein 1 (TYP1) catalyzes the oxidation of 5,6-dihydroxy indole-2-carboxylicacid (DHICA), and hydroxylation of tyrosine to 3,4-dihydroxyphenylalnin (DOPA) (monophenolase) and the oxidation of DOPA to dopaquinone (diphenolase) in mice [76,80]. But this activity has been questioned in humans. Tyrosinase is structurally designed to store two copper ions in its active site for catalytic activity. Potentially chelating copper, extracts may limit tyrosinase activity in the skin, which would prevent melanogenesis. [81]. Tyrosinase-related protein 2 (TRP2) is a tautomerize. Melanosomes are the sites of activity for the three enzymes, all of which are metal-containing glycoproteins. Furthermore, melanocyte inducing transcription factor (MITF) is a DNA-binding transcription factor that regulates melanocyte proliferation, differentiation, and melanogenesis [78,79]. MITF is responsible for regulating the expression of these enzymes. Thus, the downregulation of melanogenesis-related proteins is one way to investigate the anti-whitening effect. In recent, there are no reports on potential regulation of melanogenesis of ADS. The purpose of present study was to confirm inhibitory effects of ADS on melanogenesis underlying mechanism.7 0Item Restricted Synergistic Effect of Nano Silver Fluoride (NSF) with L-Arginine on Remineralization of Early Carious Lesions: an in Vitro Study(2023) Albahoth, Ahmad; Park, Jeong WonAlthough different dental anticarious agents have been introduced over the years. The prevalence of dental caries remains prevalent worldwide. Therefore, effective alternative approaches to the existing ones are still needed. The aim of the study was to investigate and compare the remineralizing and staining effects of nano silver fluoride with L-arginine (NSF+ Arg) on artificially demineralized permanent enamel lesions with other experimental groups, including nano silver fluoride (NSF), silver diamine fluoride (SDF), and sodium fluoride varnish (NaF). NSF and NSF + Arg formulations were prepared and characterized with transmission electron microscopy (TEM) and particle size analysis. Demineralized human enamel specimens were allocated randomly to five groups of 15 specimens each. Group I received a topical application of a 2.5 % NaF Varnish (FluoriMax, Elevate Oral Care, West Palm Beach, FL, USA). Group II received a topical application of a 12% SDF (Dengen Dental, Bahadurgarh, Haryana, India). Group III received a topical application of NSF solution (lab made). Group IV received a topical application of NSF + Arg solution (lab made). Group V received deionized water that served as a control group. After applying the test materials, all the specimens underwent a 10-day pH-cycling model. The surface morphology, color parameters, mineral density, and surface microhardness (SMH) were assessed on each enamel specimen using scanning electron microscopy (SEM), digital spectrophotometry, micro-computed tomography (micro-CT), and Vickers microhardness tester, respectively. TEM analysis of both NSF + Arg and NSF formulations revealed relatively mono-dispersed spherical silver nanoparticles with diameters ranging from 3 to 18 nm. SEM examination showed the smoothest enamel surface in the NSF + Arg group and the roughest in the control group. Among the tested groups, only the group treated with SDF (Group II) exhibited a significant black staining of enamel specimens, as indicated by a higher ΔE value (57.84 ± 1.84). In contrast, the remaining groups (I, III, IV, and V) demonstrated lower ΔE values (3.18 ± 1.56, 3.94 ± 1.35, 3.60 ± 1.17, 2.27 ± 0.52), respectively. The %SMH for groups I, II, III, IV, and V showed an increase of 30.6%, 37.7%, 28.1%, 41.8%, and 1.6%, respectively, with no statistically significant differences among the tested groups except for the control group. Among the experimental groups, NSF + Arg exhibited the highest mineral gains and % remineralization, but there were no statistically significant differences. In conclusion, judging by our results, the NSF + Arg formulation could serve as an alternative approach to SDF. This is due to its ability to remineralize early carious lesions without causing black staining.13 0Item Restricted Antioxidant and Antimicrobial Activity of Boswellia Serrata Extract for Cosmetic Ingredient(2023-05-30) Alraddadi, Bssmah Ghazi m; Hyun-Jae, ShinBoswellia serrata resin, which is an important source of gum oleoresin known as Indian frankincense and is well documented for its pharmaceutical properties due to its chemical structure, antibacterial and antioxidant properties, and the presence of several compounds such as polyphenols, phenols, and terpenoids. In the experimental study, it was observed that Boswellia Serrata resin extracts in- hibited antibacterial activity in all strains for the relevant concentrations. The diameter of the zone of inhibition for the B. serrata extract for S. epidermidis ranged from 13.3±0.58 to 10.3±0.58 mm, for M. furfur from10.6±0.58 to 9±0 mm, for M. pachy- dermatis from13.25±0.35 to 9.75±1.06 mm, and for C. acnes from 11.83±0.29 to 9.5±0 mm in the anaerobic jar. antioxidant activity was measured with DPPH It was confirmed that there was high- er activity in the Water Fr. compared to the Other fractions; respectively, Water Fr. IX showed the highest scavenging activity 902.19 ± 35.53 µg/mL, Ethyl acetate Fr. 20436 ± 652.19 µg/mL ,70% EtOH Fr. 8627.74± 369.22 µg/mL, and the Hexane Fr. Shows No scavenging activity. According to ABTS assay, the Water fraction demonstrated the maximum scavenging activity with a scavenging activity of 1845.08 ± 2265.74, followed by the ethyl acetate fraction with a scavenging activity of 12167.16 ± 8152.82 µg/mL. polyphenol and flavonoid content in the Water Fr. was the highest; it reached TPC 32.15 ± 0.75 ⅿg/mL and TFC 20.29 ± 1.47 ⅿg/mL. This study shows that the Boswellia serrata resin have some biological activities, and if they differ in terms of effectiveness and activity, they can be considered a good component of cosmetic products.32 0Item Restricted A highly sensitive lateral flow immunoassay for the rapid and on-site detection of enrofloxacin in milk(Frontiers in Nutrition, 2022-10-24) Alhammadi, Munirah; Yoo, Jingon; Sonwal, Sonam; Park, So Young; Reddicherla, Umapathi; Oh, Mi-Hwa; Huh, Yun Suk; Huh, Yun SukEnrofloxacin (ENR) is a veterinary antibiotic used to treat bacterial infections in livestock. It chiefly persists in foods and dairy products, which in turn pose severe risks to human health. Hence it is very important to detect the ENR in foods and dairy products to safeguard human health. Herein, we attempted to develop a single-step detection lateral flow immunochromatographic assay (LFIA) using gold nanoparticles (AuNPs) for the rapid and on-site detection of ENR in milk samples. An anti-enrofloxacin monoclonal antibody (ENR-Ab) was conjugated with AuNPs for the specific detection of ENR in milk samples. For sensitivity improvement, many optimization steps were conducted on LFIA test strips. The visual limit of detection (vLOD) was found to be 20 ng/ml with a cut-off value of 50 ng/ml in the milk samples. The obtained LOD and cut-off value were within the safety limit guidelines of the Ministry of food and drug safety, South Korea. The test strip showed negligible cross-reactivity with ENR analogs, and other components of antibiotics, this indicates the high specificity of the LFIA test strip towards ENR. The designed test strip showed good reliability. The visual test results can be seen within 10 min without the need for special equipment. Therefore, the test strip can be employed as a potential detection strategy for the qualitative on-site detection of enrofloxacin in milk samples.6 0Item Restricted The Impact of Entrepreneurship Education on Entrepreneurial Intention: The Mediating Role of Attitude Towards Entrepreneurship and The Moderating Role of Risk Propensity(Saudi Digital Library) AYESHA FARHAN FAHAD ALAQEEL; Advisor Prof. Junghyun Yoon . Prof. Alisher DedahanovThe real challenge for young people in today's economic and social environment is the acquisition and development of entrepreneurship-related skills to translate entrepreneurship into desirable employment choices. The field of higher education can play an important role in bridging the gap between theoretical and practical entrepreneurship by providing specific training on entrepreneurship, and higher education institutions will enhance the entrepreneurial will of these young minds and provide a platform You can play a role. We help students become aware of entrepreneurial opportunities and gain insight through regular interactions with already successful entrepreneurs. This study examines the effects of innovation and entrepreneurship education on entrepreneurship, especially attitudes toward entrepreneurship and risk taking. It aims to investigate the role of inclination. This study adopted a quantitative research approach as a survey design. The population for the study consists of 350 responses and data is collected in Saudi Arabia. Although the questionnaire was written in English, it was translated into Arabic to obtain accurate data as Arabic is the native language of Saudis. In the study, we develop a model that presents attitudes towards entrepreneurship as a mediator between entrepreneurship education and entrepreneurial intentions, and use risk-taking propensity as a moderator between attitudes towards entrepreneurship and entrepreneurial intentions. Several standard analysis techniques were used, such as factorial, correlation, reliability, and hierarchical regression analysis. Our results indicate that entrepreneurship education is positively related to attitudes towards entrepreneurship. Additionally, the findings suggest that attitudes toward entrepreneurship promote entrepreneurial intentions. In addition, hierarchical regression analysis indicates that risk appetite does not mitigate the link between attitudes towards entrepreneurship and entrepreneurial intentions. A potential reason for this result is that when individuals develop positive attitudes about entrepreneurship, they may overlook risk factors because of their positive thoughts about starting a business. In other words, individuals with positive entrepreneurial attitudes may not consider the role of risk in starting a business because of their preoccupation with the business.24 0Item Restricted study on characterization of multi-layered polymer joining using laser(Saudi Digital Library) ALANZI KHALID ANWAR; choi, hae woonالتعلم على جهاز بلمير ليزر وطريقة الحام PC و ال ABS وMM2 0Item Restricted Antioxidant activity of Ajwa date extract for cosmetic ingredient(Saudi Digital Library) KHLOOD LAFI DAWI ALHARBY; Hyun-Jae ShinAjwa date fruit (DF) and Ajwa date fruit seed (DFS) are essential sources of phe- nolic compounds with many health benefits. To investigate the potentials of DF and DFS in neutralizing free radicals, they were extracted by three different methods: 100% ethanol, 70% ethanol, and hot water extract, and the results showed a difference be- tween them in terms of the effectiveness of antioxidants and the number of phenolic compounds. In the experimental study, it was observed that all three extracts containing flavonoids had antioxidant activity, and found that this activity differed between each extract in terms of concentration, where the 100% ethanolic extract of the seeds (DFS3) showed the most significant activity in the hydroxyl radical family, when using antioxidant assay DPPH and ABTS. It was also found that these extracts had different amounts of phenolic compounds, and the hot water extract of the fruit (DF1) recorded the highest content of phenolic compounds, up to 3008.66 μg/g. This study shows that the fruits and seeds of the Ajwa date palm have a good re- turn in terms of natural compounds that showed some biological activities, and although they differ in terms of effectiveness and activity, they can be considered a good component of cosmetic products.19 0Item Restricted The Effect of WOM and e-WOM on Brand Trust and Purchase Intention in Luxury Brand Purchase contexts: Compared with Korean and Saudi Arabia(Saudi Digital Library) DEEMA MOHAMMED ALTHEYAB; Chuljae ChoiThe future portends market alteration, increased competition, and a demand for creative and aggressive marketing practices. As traditional word of mouth evolved into a new form as electronic word of mouth, the influence of electronic word of mouth (e-WOM) on customer purchase intention has long been known, and the emergence of social media fads have created a new perspective to e-WOM through enabling users to communicate with their existing online platforms on the internet, users can exchange their opinions and experiences about products or services with others, either people who they already know such as friends or complete strangers. While e-WOM has an impact on customers, and their purchase intentions, researchers are undertaking research to explore WOM and e-WOM impacts on purchase intention. However, few studies have investigated cross cultural and comparative differences between countries according to such type of studies. Therefore, the present study explores the impact of WOM and e-WOM with the mediating effect of brand trust and the moderating effect of brand image of luxury brands of South Korean and Saudi Communities, Brand Trust, Brand image, and Purchase Intention comparing which type of the WOM has the highest impact. In this regard, we proposed a model containing five variables (WOM, e-WOM, Brand Trust, Luxury Brand Image, and Purchase Intention). Some of the key findings include that the relationships between the variables for both groups were positive (WOM, e-WOM, Brand Trust, Luxury Brand Image, Purchase Intention), except the e-WOM -brand trust relationship which was negative for the Korean group and the WOM -brand trust which was negative for the Saudi group.3 0