Dalat University Journal of Science / Tạp chí khoa học Đại học Đà Lạt
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THE MEDIATING ROLE OF ENVIRONMENTAL KNOWLEDGE SHARING ON THE IMPACT OF GREEN LEADERSHIP ON INNOVATION IN VIETNAMESE SMALL AND MEDIUM ENTERPRISES
Get PDFWith environmental sustainability gaining significance, firms require green leadership to drive the adoption of eco-innovations through appropriate culture-building. This quantitative study uses upper echelons theory to analyze green innovation levels in Vietnamese small and medium enterprises (SMEs) and to assess intermediary mechanisms that transmit strategic leaders’ influence. Results of partial least squares structural equation modeling (PLS-SEM) provide strong empirical support for the hypotheses that environmental knowledge sharing practices mediate the impact of green leadership behaviors on higher performance in green product and process innovation. Specifically, knowledge exchange through cross-functional collaborations and external partnerships explains the effect of leadership. Findings respond to calls for research on green innovation drivers in emerging markets such as Vietnam, where institutional pressures for ecological responsibility remain underdeveloped. Furthermore, identifying actionable transmission mechanisms informs policy guidelines regarding interventions necessary to nurture sustainable innovation. This study offers multi-level theoretical and practical contributions
DIGITAL BADGES AS REWARDS IN SCIENCE EDUCATION: STUDENTS’ PERCEPTIONS AND EXPERIENCES
Get PDFSeveral studies have reported positive effects of digital badges on students’ academic performance and behavior. A digital badge serves as an indicator of an accomplishment or skill that can be showcased, accessed, and verified online. The researcher investigated how students perceive digital badges as rewards in a biology course through a phenomenological study. Gamified lesson plans and students’ portfolios were used to implement gamification and award digital badges. The study involved Filipino Grade 12 STEM students (n = 41) from a single intact class, and interviews were conducted with a subset of 10 students. By analyzing student responses in their portfolios and interviews, four key themes of digital badges were identified: class participation, learning outcomes, time management, and social interaction. The results revealed that these themes were influenced by factors such as competition, a sense of accomplishment, self-improvement, status recognition, and evidence of achievement. It was found that, while digital badges can be beneficial for high-performing students, they may have detrimental effects on low-performing students. The researcher recommended that the identified themes and their underlying drivers be considered when developing digital badges and in future studies on digital badges and gamification
DISTRIBUTION AND POTENTIAL OF CAMELLIA SPP. IN THE CENTRAL HIGHLANDS, VIETNAM, FOR DEVELOPING HIGH-VALUE PRODUCTS IN THE FOOD INDUSTRY
Get PDFThis article focuses on the potential use of yellow camellias in the food technology industry by analyzing and synthesizing information from previous publications. Many rare species of the genus Camellia have been discovered recently in the Central Highlands of Vietnam, including 10 new species discovered in Lam Dong Province between 2012 and 2016. These 10 species account for 55.55% of the 18 species growing naturally in the Central Highlands and demonstrate the diversity of Camellia in the region. The flowers range from light yellow to orange to deep yellow in color. The survival rate of cuttings is 72.24%–83.33%, and the rooting rate when seeds are sown approaches 100%. Yellow camellias do not contain caffeine. The main active ingredient is polyphenol, with a content of 5.22%–30.11% (mg GAE/100 g DW). Camellia extract does not cause acute toxicity and has a blood sugar-lowering effect. Vietnam has much experience growing green tea; the total green tea growing area is 131,200 hectares. The average annual yield is 6.90 tons of fresh leaves per hectare, and the current export market to 60 countries is the basis for expanding the yellow camellias growing area. The Central Highlands has great potential as a stable source of raw materials to create fermented beverages, tea powder, tea oil, and colorants
CONDITIONS FOR GRAPHS ON n VERTICES WITH THE SUM OF DEGREES OF ANY TWO NONADJACENT VERTICES EQUAL TO n-2 TO BE A HAMILTONIAN GRAPH
Get PDFLet G be an undirected simple graph on vertices with the degree sum of any two nonadjacent vertices in G equal to . We determine the condition for G to be a Hamiltonian graph
ISOLATION AND STRUCTURAL IDENTIFICATION OF TRITERPENE COMPOUNDS FROM THE LEAVES OF RUBUS ANNAMENSIS CARDOT COLLECTED IN LAM DONG PROVINCE
Get PDFFrom the leaves of Rubus annamensis Cardot collected in Lam Dong Province, two triterpene compounds were isolated and identified as niga-ichigoside F1 (2α,3β,19α,23-tetrahydroxy-urs-12-en-28-oic acid-β-D-glucopyranosyl ester) and ursolic acid (3-beta-3-hydroxy-urs-12-ene-28-oic acid) by using chromatographic and spectroscopic methods (IR, 1H-NMR, 13C-NMR, DEPT, HSQC, HMBC, and ESI-MS). This is the first time these compounds have been isolated from Rubus annamensis
INFINITESIMAL FIELD SIZE HVL OF ISO 4037 NARROW SPECTRUM X-RAYS: SIMULATED RESULTS
Get PDFHalf-value layer (HVL) measurement is the method most often used to validate an X-ray reference field as defined in ISO 4037. This work presents Particle and Heavy Ion Transport code System (PHITS) simulated values of HVL and their standard deviations for an infinitesimal radiation field size. The HVL values, calculated from simulated values of air kerma at a detector position for various radiation field sizes, were extrapolated to an infinitesimal field size for different ISO 4037 narrow spectrum X-ray beam qualities at two distances from an X-ray source
AN ASSEMBLED SKETCH OF PLACE NAMES IN LAC DUONG DISTRICT, LAM DONG PROVINCE
Get PDFLac Duong District, located in Lam Dong Province, is traditionally inhabited by the Cơ Ho people (also known as the K’Ho), who are divided into two major subgroups: Chil and Lạch. The district is noted for its unique cultural and historical features, partly reflected in its place names. This study, conducted over a year in 2023, involved selecting and analyzing names of places in Lac Duong District by qualitative methods, statistical analysis, linguistic analysis, and place-name grouping. The paper classifies these names into four groups and examines the characteristics of Lac Duong District in terms of etymology, cultural space, historical period, and cultural subject. The findings provide a concise, yet significant, insight into the district’s cultural and historical depth. In the context of increasing cultural and economic exchanges, this research is timely and essential for supporting the preservation and promotion of the local residents’ cultural identity
A NOVEL DATASET FOR VIETNAMESE NEW YEAR FOOD CLASSIFICATION
Get PDFFood classification has always piqued the interest of both domestic and international researchers, but numerous challenges remain. We present the dataset UIT-TASTET21, which contains over 77,000 color images of 18 traditional Vietnamese Lunar New Year dishes. We have experimented with classification using feature vectors from network architectures such as VGG16, Inception-v3, ResNet-50, Xception, and MobileNet-v2 to train support vector machines (SVMs), meeting the dataset’s challenges and laying the groundwork for the development of many optimal methods in the future that promise scientific breakthroughs in the service and commercial industries. At the same time, the authors desire to share a piece of Vietnamese cuisine’s distinctiveness with worldwide friends
AN EXPERIMENT ON THE PROPOSED ONLINE ASSESSMENT AND EXAMINATION METHOD AT DALAT UNIVERSITY
Get PDFDigital transformation is one of the key tasks of the education field. In this context, online teaching is becoming a potential solution in education to provide learners with a flexible learning environment that is independent of space and time. This trend has become even more urgent as the world has just experienced the global COVID-19 pandemic. Along with online teaching are methods of online assessments and examinations. The biggest challenges to online assessments and examinations are internet speed, authentication of the examinee’s identity, and test authenticity, especially for classes with large numbers of students. In this article, we propose an online oral exam process that can be applied to a large class but still ensures seriousness, fairness, and objectivity. Experiments conducted in 11 courses taught and assessed at Dalat University during the second semester of the 2020–2021 school year and the first semester of the 2021–2022 school year are discussed to illustrate the process
CONSERVATION STATUS AND RESEARCH ON PROPAGATION OF CAMELLIA PIQUETIANA IN LAM DONG PROVINCE, VIETNAM
Get PDFCamellia piquetiana, one of the endemic species of Vietnam, is classified as Critically Endangered (CR) by the IUCN. A reassessment of its conservation status and research into propagation methods are essential for its conservation. Our survey recorded 246 mature individuals in the wild at three locations in Lam Dong Province: Bao Loc City, Bao Lam District, and Da Huoai District. The conservation assessment for this species, determined with GeoCat software, is still CR. Propagation by partially uncoated seeds had a higher propagation efficiency than by coated seeds. The germination percentage was 92.22%; the seeds began germination after 11 days and finished after 29.33 days. The results showed that stem cuttings immersed in a concentration of 500 ppm indole-3-butyric acid for 10 minutes with a 100% coir substrate gave the highest survival percentage (90.00%), rooting percentage (86.67%), average number of roots (4.54), root length (4.86 cm), and rooting index (21.98) after 90 days