Dalat University Journal of Science / Tạp chí khoa học Đại học Đà Lạt
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A STUDY OF SUBJECTIVE CAREER SUCCESS AND PERSONALITY TRAITS OF MIDDLE-LEVEL HOTEL MANAGERS IN THE HOSPITALITY INDUSTRY
Get PDFThe present study investigates whether the Big Five personality traits can predict subjective career success. It uses socio-analytic and career congruence theories to predict individual outcomes, such as subjective career success. Data were obtained from 33 four- and five-star resorts and hotels operated by international and domestic chains in Vietnam. A total of 391 middle-level hotel managers were approached, using specific quotas for age, gender, education, and work experience. The final valid sample included 285 of the 297 respondents willing to participate. Confirmatory factor analysis and structural equation modeling were employed to investigate the hypothesized correlations between the constructs. Extraversion, conscientiousness, openness to experience, and agreeableness were found to positively predict, and neuroticism to negatively predict subjective career success. This result extends our understanding of the role of personality elements in determining career success. It also confirms the necessity of congruence between career success and personality. This result is crucial for those who provide career counseling and advice because, by knowing the connection between personality traits and subjective career success, they can better guide middle-level hotel managers in deciding on a relevant and appropriate career path
A CONDITION FOR LOCAL INTEGRABILITY OF NEGATIVE POWERS OF SMOOTH FUNCTIONS IN TWO VARIABLES
Get PDFLet f(x,y) be a smooth real-valued function defined in a sufficiently small neighborhood U of the origin such that f(0,0) = 0. We study the set of all positive ε for which \int_{U}|f(x,y)|^{-\varepsilon}dxdy < \infty. We provide a condition for the Newton polygon characterization such that this set can be expressed in natural ways using the Newton polygon of f
STRUCTURAL AND MECHANICAL PROPERTIES OF 2D GRAPHENE: A STUDY OF MOLECULAR SIMULATIONS
Get PDFA graphene model consisting of 12,000 atoms is yielded by molecular dynamics simulation in two-dimensional space. The structural evolution of the graphene model is analyzed in terms of total energy per atom, heat capacity, radial distribution function, coordination number distribution, bond angle distribution, and visualization. The results show that spontaneous melting of the graphene model occurs at approximately Tm = 6500 K. In addition, our simulation of the atomic configuration shows that the coexistence of crystalline and melted regions near the melting temperature confirms the first-order behavior of the phase transition. The Lindemann criterion for the 2D case is calculated and used to observe the appearance of liquid-like atoms. The atomic mechanism is analyzed based on the occurrence and growth of these liquid-like atoms. The Young’s modulus of the graphene model at an uniaxial strain rate of 108 s-1 is 1.014 TPa, indicating good agreement with the experimental data. This research brings substantial practical benefits to industries looking to leverage the unique thermal and mechanical characteristics of graphene
EFFECT OF LOCALLY ISOLATED SCENEDESMUS SP. TN1 ON BIOMASS PRODUCTION AND NUTRIENT REMOVAL FROM COOKING COCOON WASTEWATER: EFFECTS OF INITIAL ALGAL CELL DENSITY AND TEMPERATURE
Get PDFScenedesmus sp. TN1, a local freshwater microalga, was cultivated in cooking cocoon wastewater. The effects of initial algal cell density and temperature on microalgae growth and the removal of total nitrogen (T-N), total phosphorus (T-P), and chemical oxygen demand (COD) were studied. The initial algal cell densities were 5, 10, 15, and 20 mg/l. The experimental temperatures varied from 20 °C to 30 °C. The growth rate increased with the increase in initial algal cell density up to 15 mg/l and was statistically stable thereafter. A similar trend of total nitrogen, total phosphorus, and COD removal efficiency was observed. The optimum temperature for microalgae growth and nutrient removal was 30 °C. After 9 days of cultivation, Scenedesmus sp. TN1 exhibited nutrient removal efficiencies of 88.28%, 82.91%, 92.01%, and 89.16% for T-N, T-P, biological oxygen demand (BOD5), and COD, respectively. The maximum biomass production and nutrient removal efficiencies of Scenedesmus sp. TN1 were observed at cultivation conditions of 15 mg/l initial algal cell density at 30 °C. This study compiled information on the cultivation conditions for cooking cocoon wastewater treatment practices
FACTORS INFLUENCING CONSUMER INTENTION TO PURCHASE REMANUFACTURED PRODUCTS WITHIN THE VIETNAMESE CIRCULAR ECONOMY
Get PDFThis study extends the theory of planned behavior (TPB) by incorporating environmental knowledge, environmental beliefs, and perceived value to understand Vietnamese consumer purchase intentions towards remanufactured products. The research aims to offer insights that support Vietnam’s transition towards a circular economy. Data were collected from 277 respondents using a structured survey, which assessed the relationships between environmental knowledge, beliefs, attitudes, perceived value, social pressure, product availability, and purchase intentions. Partial least squares structural equation modeling (PLS-SEM) was employed to analyze the hypothesized relationships. The results show that attitude has the strongest positive influence on purchase intention, driven primarily by environmental beliefs and knowledge. Additionally, product availability also significantly impacts purchase intention. The findings emphasize the importance of knowledge dissemination and product accessibility in fostering sustainable consumption behaviors. These insights suggest that policymakers and businesses should prioritize strategies that increase environmental knowledge, foster positive attitudes towards remanufactured products, and ensure their accessibility, thereby promoting sustainable consumption habits and advancing the circular economy in Vietnam
THE IMPACT OF CORPORATE SOCIAL RESPONSIBILITY ON CUSTOMER LOYALTY AND THE MODERATING ROLE OF CUSTOMER INCOME: A CASE STUDY OF THE HOSPITALITY INDUSTRY IN PHU QUOC CITY, VIETNAM
Get PDFThis study explores the impact of corporate social responsibility (CSR) on tourists’ satisfaction and loyalty, focusing on factors related to corporate social and economic outcomes. It also examines how consumer income moderates the relationship of CSR on customer loyalty, customer satisfaction, and corporate reputation. A mixed-methods approach was employed, starting with expert interviews and followed by a questionnaire survey targeting Vietnamese tourists aged 18 and above staying at 4- and 5-star hotels in Phu Quoc City, Vietnam. A random sampling technique yielded 271 valid questionnaires for analysis, and partial least squares structural equation modeling was employed to evaluate the model and test hypotheses. The results show that CSR positively influences customer loyalty, customer satisfaction, service quality, and corporate reputation. Both service quality and corporate reputation were found to positively affect customer satisfaction and loyalty, with customer satisfaction having the strongest influence on customer loyalty. Importantly, consumer income was shown to positively moderate the impact of CSR on perceived corporate reputation. These results provide valuable insights for identifying CSR factors that can improve customer satisfaction and loyalty. Additionally, they highlight service quality and corporate reputation as key areas for enhancing customer satisfaction and loyalty. The study also sheds light on the moderating role of income, a topic that has been relatively underexplored in hospitality management research. The managerial implications discussed offer practical guidance for hotel businesses seeking to develop strategies to attract and retain customers
ANALYZING PATTERNS OF CONGRATULATORY STRATEGIES IN VIETNAMESE FACEBOOK WEDDING ANNOUNCEMENTS
Get PDFThis study explores the patterns of congratulatory strategies related to wedding rituals on Facebook, a prominent platform within the Vietnamese community. With the increasing integration of information technology, Facebook has become a vital space for expressing emotions and fostering connections. Employing a descriptive research design, the study integrates both quantitative and qualitative approaches to data analysis. Quantitatively, the frequency of semantic formulas used in congratulatory messages was calculated and compared across engagement and wedding announcements, with descriptive statistics applied to interpret the data. Qualitatively, an ethnographic approach was used to explore and analyze these strategies through observation and discourse analysis, identifying recurring themes and patterns. The analysis reveals seven distinct patterns, including two single-strategy patterns–using illocutionary force indicating devices (IFIDs) and offering good wishes–and five combined-strategy patterns that integrate IFIDs with offering good wishes, giving compliments, joking, and expressing positive emotions. These findings highlight linguistic and cultural features that showcase how Vietnamese users express care, pleasure, and affection in congratulatory comments, reflecting the preservation of cultural traditions in a digital context. This study contributes to the sociolinguistics field by providing insights into the intersection of social media and cultural expression, offering a novel perspective on Vietnamese culture in online communication. While the study is limited by the availability of data specific to Facebook wedding announcements, its findings offer valuable implications for understanding the role of social media in shaping and sustaining cultural practices
VALIDATION OF SINGLE NUCLEOTIDE POLYMORPHISMS IN RIBOSOMAL DNA INTERNAL TRANSCRIBED SPACER SEQUENCES OF WOLFFIA MICROSCOPICA (GRIFF). KURZ
Get PDFDuckweeds are aquatic plants with 35 species and 2 hybrid species belonging to five genera (Spirodela, Landoltia, Lemna, Wolffiella, and Wolffia) within the Lemnaceae family. The only surviving Wolffia microscopica (Griff.) Kurz (accession number 9276) was lost from all collections in 2009. Fortunately, some accessions of this species were rediscovered in Sughad, India, and Bangladesh in 2014. The purpose of this study is to identify single nucleotide polymorphisms (SNPs) in the internal transcribed spacer sequence (ITS) region of 10 Wolffia microscopica accessions. In all, 31 plasmids from 8 accessions were investigated, resulting in 15 plasmid variants and 24 SNPs. However, based on the outcome of the SNP evaluation techniques (restriction enzyme, polymerase chain reaction analysis using certain SNPs, and web-based allele specific primer design primers), these SNPs were not Wolffia microscopica subspecies-specific. Therefore, for the 10 investigated Wolffia microscopica accessions, the ITS region works well for species-level classification but is not appropriate for subspecies level classification
THE HALOPHYTE PLANT RESOURCES OF THE FOREDUNES ON THE SOUTH-CENTRAL COAST OF VIETNAM
Get PDFHalophytic plant resources play a vital role in meeting the needs of local people, and they have potential applications in nutrition and sustainable agriculture. Ethnobotanical surveys were conducted on foredunes at 41 study sites in 8 provinces of the south-central coastal region of Vietnam. The findings show that the majority of halophytic plants fall into the following resource groups: traditional medicine (45.13%, 88 species), food, (13.85%, 27 species), woody plants (4.62%, 9 species), and ornamentals (4.10%, 8 species). In comparison, 26.67% (54 species) have not been documented for specific uses. Halophytic resources account for 73.34% of the surveyed species, highlighting their significant ethnobotanical value. Cultivating these natural resources can benefit coastal communities by supporting local socio-economic development while promoting the environmental sustainability of the coastal soils and climate
GROUP VELOCITY DISPERSION CONTROL BY SUSPENDED- CORE SOFT-GLASS FIBER FILLED WITH CARBON DISULFIDE
Get PDFAn enhanced group velocity dispersion (GVD) control with suspended core fiber (SCF) has been investigated using numerical simulation based on the finite element method. It requires an SCF made of lead-bismuth-gallium-oxide glass with three air holes filled with carbon disulfide (CS2). Unlike unfilled fibers, CS2-filled SCFs can achieve small slopes of the effective refractive index curves using the fundamental modes, resulting in flat group velocity dispersion in the low group velocity region. We also found that the ratio between the width of the bridge and the core radius can affect the shift of the zero-dispersion wavelength. The proposed SCFs show excellent performance in achieving low anomalous GVD, which can offer higher efficiency in supercontinuum spectral flattening. Additionally, the structures with small normal GVD values are promising candidates for pulse stretching due to the exact balance between nonlinear effects and dispersion