Dalat University Journal of Science / Tạp chí khoa học Đại học Đà Lạt
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THE MULTILAYERED NETWORK MODEL: A NEW APPROACH TO THE STUDY OF POLITICAL INSTITUTIONS IN SOUTHEAST ASIAN HISTORY
No full textThis article develops the multilayered network model as a comprehensive analytical framework for examining the political institutions of premodern Southeast Asia. The model is designed to move beyond the established paradigms of the nation-state and the mandala system by integrating insights from history, political theory, anthropology, and archaeology. It conceptualizes Southeast Asian polities not as static, territorially bounded entities, but as dynamic systems composed of multiple layers of authority–royal, local, religious, and mercantile–interacting through fluid networks of exchange, ritual, and power negotiation. Through comparative and historical analysis of representative cases such as Srivijaya, Angkor, Đại Việt, and Malacca, this study argues that Southeast Asian governance was characterized by negotiated sovereignty and adaptive pluralism rather than centralized domination. The multilayered network framework highlights three interrelated mechanisms–interlayer negotiation, cross-network diffusion, and nodal reconfiguration–that explain how political institutions evolved and sustained their resilience over time. By formalizing these mechanisms, the model provides a new theoretical lens through which to analyze institutional continuity, regional interconnectivity, and political adaptation. The paper thus contributes to ongoing efforts to decolonize Southeast Asian historiography, offering a flexible methodological tool that bridges symbolic and material dimensions of power
DYSOXYLUM MOLLISSIMUM (SPRENG.) BLUME EX G. DON (MELIACEAE), A NEW RECORD FOR THE FLORA OF VIETNAM
Get PDFDysoxylum mollissimum (Spreng.) Blume ex G. Don is a new record for the flora of Vietnam. This species is distributed in primary and secondary forests in scattered populations at elevations of 800–1200 m above sea level in the provinces of Gia Lai and Lam Dong in the Central Highlands of Vietnam. It is most similar to Dysoxylum loureiri (Pierre) Pierre in the characters of general vegetative habit and the shape of the leaves, calyx, petals, and stamens. The investigated taxon is closely related to Didymocheton mollissimus (Spreng.) Mabb., a synonym of Dysoxylum mollissimum (Spreng.) Blume ex G. Don, in all three clustering methods used. This indicates that the investigated taxon belongs to Dysoxylum mollissimum (Spreng.) Blume ex G. Don and can be considered an ecological variety of this species
MONOMIAL IDEALS FROM A SEMIRING PERSPECTIVE
Get PDFWe formulate the theory of monomial ideals of a ring of polynomials with coefficients in a field through the theory of semirings. In particular, we focus on the theory of integrally closed monomial ideals. We prove that there exist isomorphisms of lattice-ordered semirings between the semiring of antichains of Nn equipped with the product order (of its usual order), and the semiring of monomial ideals. In the same way, we prove that there is an isomorphism between the semiring of integrally closed monomial ideals and the family of vertex sets of Nn equipped with the product order. These isomorphisms are independent of the choice of a base field for the polynomial ring
POLITICAL POLARITY AND INTERNATIONAL ORDER: CONCEPTS AND CONTEMPORARY DYNAMICS IN INTERNATIONAL RELATIONS AND VIETNAM’S STRATEGIC ADAPTATIONS
No full textThe global political system can be organized in several configurations, including multipolarity, bipolarity, unipolarity, and nonpolarity. This study applies historical and theoretical analysis grounded in political polarity theory to assess the contemporary international order. The findings reveal that current global power relations are complex, driven by the ascent of emerging powers, the relative decline of Western influence, and the impact of globalization, technological progress, and intensified competition among major states. The international system appears to be undergoing a transitional phase, involving the erosion of the previous structure and the emergence of a new configuration shaped by multiple converging forces. Although the United States retains a position of overall strategic and material superiority, it increasingly contends with challenges from China, which is aggressively expanding its influence through sweeping initiatives such as the Belt and Road Initiative. Russia’s military actions in Ukraine reflect opposition to Western influence and resistance to the United States-centric international order. Additionally, actors such as the European Union, India, and Japan are assuming more prominent roles, further contributing to the diversification of global power dynamics. The current international order displays characteristics of multipolarity while simultaneously being strongly influenced by the bipolar rivalry between the United States and China, alongside deepening political fragmentation in several domains. These evolving dynamics also shape Vietnam’s external relations, prompting the country to pursue a balanced diplomatic strategy and establish broad-based strategic partnerships with key global actors to protect its national interests while maintaining autonomy from competing power blocs
COMBINATION OF MULTILAYER Ag-Al FOR OPTICAL BIOSENSOR BASED ON SURFACE PLASMON RESONANCE
Get PDFThis work presents the simulation and experimental results of a surface plasmon resonance (SPR) sensor made of a hard polymer-clad fiber. The cladding of the fiber is removed, and then a bimetallic film of nanometer thickness is deposited around the fiber core to create a ten-centimeter-long sensing surface. An optical sensor based on thin film combinations of silver and aluminum has a detection capability of about 3×10-6 (dB/RIU), allowing high sensitivity of easily fabricated optical sensors. This leads us to believe that the proposed SPR sensor can be used to detect biological targets during the clinical diagnosis of diseases, e.g., heart disease, Alzheimer’s disease, cardiovascular disease, and stroke
OPTIMIZATION OF CULTIVATION CONDITIONS OF A NEWLY ISOLATED STRAIN CHLORELLA SP. LH2 FOR COOKING COCOON WASTEWATER TREATMENT
Get PDFCooking cocoon wastewater contains large quantities of biodegradable nutrients such as nitrogen, phosphorous, and other compounds that microalgae can consume for their growth. In this study, locally isolated Chlorella sp. LH2 was investigated as a means to remove contaminants in wastewater treatment. This alga can grow under a wide range of cultivation conditions. The results showed that Chlorella sp. LH2 grew well in cocoon wastewater and removed nutrients. The optimal cultivation conditions were determined for a variety of initial dry cell densities, temperatures, pH, and light-dark cycles. The maximum growth rate of Chlorella sp. LH2 was achieved at 25 °C, a pH of 8, a light-dark cycle of 16:08, and an initial dry cell density of 1.5 mg/l. Chlorella sp. LH2 exhibited nutrient removal efficiencies of 89.84%, 90.01%, and 93.44% for total nitrogen, NH4+-N, and total phosphorous, respectively. The high BOD5 and COD removal efficiencies of 91.78% and 87.34%, respectively, indicate that Chlorella sp. LH2 can be considered an ideal microalga to treat cooking cocoon wastewater and is worthy of further applications
THEORETICAL STUDIES ON THE MAGNETIC, ELECTRICAL, AND OPTICAL PROPERTIES OF LEAD-FREE FERROELECTRIC Ba(ZrTiO) MATERIALS WITH MANGANESE DOPING
Get PDFIn this study, we conducted a density functional theory investigation of the structural, electronic, magnetic, and optical properties of manganese-doped lead-free ferroelectric Ba(Zr0.2Ti0.8)O3 (BZT) materials. The electronic structure calculations revealed that pristine BZT material behaves as a p-type semiconductor with direct and indirect bandgaps of 3.18 eV and 2.08 eV, respectively. Upon Mn doping, the bandgap values converge to zero, indicating a transition from semiconductor to metal behavior. Additionally, the asymmetrical spin-polarized density of states and significant magnetic moments, determined through Mulliken population analysis, suggest the induction of magnetism in the BZT material due to Mn doping. Magnetic moments of 0.98 µB/f.u., 0.57 µB/f.u., and 0.87 µB/f.u. were observed when Mn substitutes into Ba, Ti, and interstitial sites, respectively. Furthermore, we observed substantial enhancements in dielectric constants and changes in other properties such as refractive index, loss function, and reflectivity upon Mn doping, suggesting alterations in the optoelectronic properties of the materials. Our findings contribute to the understanding of transition metal-doped lead-free ferroelectric BZT materials and provide more information for the development of future smart electronic and optoelectronic devices
HUMAN CAPITAL AS THE SOURCE OF ECONOMIC GROWTH
Get PDFThis paper revisits the theoretical framework of endogenous economic growth by considering models where human capital accumulation is at the center of the growth process. Our work is in line with Lucas (2015), who calls for not giving “too large a role to exogenous technological change” (p. 86) while advocating that “the contribution of human capital accumulation to economic growth deserves a production function of its own” (p. 87). The main finding of our research provides the long-term behavior of economies, where our main results locate and extend these discussions to infinite-horizon models in several ways.
Correction Notice
Correction to Tran, N. T. and Thai, H. H. (2023). Human capital as the source of economic growth. Dalat University Journal of Science, 13(4S), 30–41.
As initially published, this article contained an error in the author list. In the corrected version of the article, Thai Ha Huy [University of Évry (University of Paris-Saclay), Évry, France] has been removed from the author list as the authorship of the article belongs solely to Tran Nhat Thien [The Faculty of Economics and Business Administration, Dalat University, Lam Dong, Vietnam].
The author list of this article has been corrected at the request of the Editor-in-Chief because the author list was originally incorrect. In November 2023, the Dalat University Journal of Science (DLU-JOS) became aware that the author/contributor list presented in the article was incorrect. The error was reported to the DLU-JOS by the two authors themselves. One of the authors was not aware that his name had been included in the author list of the article, and both authors agreed to request that the article be retracted. In accordance with the international guidelines established by the Committee on Publication Ethics, of which the DLU-JOS is a member, we have determined that these are not grounds for retraction. We have determined that the authorship of the article was disputed but that no reason exists to doubt the validity or reliability of the findings. Therefore, a correction to the author list should sufficiently address the concerns raised by the two authors.
To ensure transparency and the accuracy of the scholarly record, we have decided to issue a formal correction to the author/contributor list of the article with the belief that the two authors have provided appropriate proof that such a correction is justified.
The authors have agreed to this formal correction notice.
The DLU-JOS regrets this incident and extends its apologies to its readers
AIRPORTS AS AN ATTRACTION: A CASE STUDY OF CHANGI AND INCHEON INTERNATIONAL AIRPORTS
Get PDFAirports in Singapore and the Republic of Korea have higher passenger traffic than those in neighboring countries. This may be because Changi International Airport in Singapore and Incheon International Airport in Korea are not only functional but also attractions. Such airports are beneficial during national crises, such as pandemics and economic downturns, because they serve as tourist attractions. This study examines the services offered by these two airports to identify factors that could help Vietnamese airports enhance their services. The results indicate that Vietnamese airports should provide cultural amenities consistently across all terminals. However, as Changi and Incheon International Airports are larger than Vietnam’s airports, future studies should focus on smaller airports, such as Tan Son Nhat Airport, to investigate methods to attract tourists
CAMELLIA HOAANA (THEACEAE, SECTION CORALLINA), A NEW SPECIES FROM BU GIA MAP NATIONAL PARK IN SOUTHERN VIETNAM
Get PDFCamellia hoaana, a new species of the Camellia sect. Corallina (Theaceae) from Bu Gia Map National Park, Vietnam, is described and illustrated. Morphological features of this species are young branches pubescent and glabrescent. Leaves elliptic to obovate-elliptic; apex bluntly cuspidate, base wide cuneate; above dark green, shiny and glabrous; below paler green and sparsely pubescent along midrib; petiole sparsely pubescent. Flowers solitary or geminate, axillary or terminal; pedicel pubescent. Bracteole 1 (or none),pubescent on both sides, persistent. Sepals 4–5(–6), pubescent on both sides, persistent. Petals 5–6, white, outermost 1–2 pubescent at the apex on both sides, the rest glabrous on both sides. Androecium numerous, 2–3 whorls, glabrous. Ovary 3-locular, white silky tomentose; styles 3, free to the base, glabrous. Capsule subglobose, sparsely pubescent, furfuraceous. Seeds 1–2 per locule, semiglobose or globose, densely brown villous. This new species is assessed as Data Deficient (DD) according to the IUCN categories and criteria