Dalat University Journal of Science / Tạp chí khoa học Đại học Đà Lạt
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INVERSE VARIATIONAL INEQUALITIES AND SECOND-ORDER DYNAMICAL SYSTEMS
Get PDFWe consider the inverse variational inequality problem in finite-dimensional space and study its associated second-order dynamical system. In particular, we propose a second-order dynamical system whose trajectory converges exponentially to the solution of the inverse variational inequality problem under the Lipschitz continuous and strongly monotone condition
TWIST-SPUN KNOTS OF TWIST-SPUN KNOTS OF CLASSICAL KNOTS
Get PDFA k-twist-spun knot is an (n+1)-dimensional knot in the (n+3)-dimensional sphere that is obtained from an n-dimensional knot in the (n+2)-dimensional sphere by applying an operation called a k-twist-spinning. This construction was introduced by Zeeman (1965). In this paper, we show that the m2-twist-spinning of the m1-twist-spinning of a classical knot is a trivial 3-knot in S5 if gcd(m1, m2) = 1. We also give a sufficient condition for the m2-twist-spinning of the m1-twist-spinning of a classical knot to be nontrivial
EFFECT OF CULTURE CONDITIONS ON RECOMBINANT GFP PRODUCTION BY ARABIDOPSIS THALIANA (L.) HEYNH. HAIRY ROOTS
Get PDFRecombinant proteins are produced by various expression systems. In the present study, the production and stability of green fluorescent protein (GFP) produced by Arabidopsis thaliana hairy roots were investigated. The parameters included the culture media and shaking speeds. The results showed that the B5 medium supplemented with 3% sucrose was the best among the three studied media for hairy root growth and GFP production, as the hairy roots exhibited a preference for nitrate over ammonium salt as a nitrogen source. GFP production increased from two to four weeks of culturing in the B5 medium, in which hairy root line 30 reached approximately 27 mg/L GFP after four weeks. The lower shaking speed of 60 rpm was better for GFP production and for the stability of the His-tag attached to GFP. These results provide new insights into recombinant protein production by the hairy roots of Arabidopsis thaliana. This will pave the way for better optimization of recombinant protein production using plant cell systems, which could reduce the immunological response when these recombinant proteins are produced and used for therapeutic applications in animals or humans
COMPARISON OF LEGAL CONSUMER PROTECTION SYSTEMS IN E-COMMERCE TRANSACTIONS TO SUPPORT DIGITAL ECONOMIC GROWTH IN INDONESIA
Get PDFThe e-commerce industry in Indonesia is growing rapidly amidst the slowdown in the country\u27s economy. Moreover, most of the e-commerce business players in Indonesia are small, micro, and medium scale (SME). Consumers in e-commerce transactions have a greater risk of loss than business actors or merchants. In other words, consumer rights in e-commerce transactions are very vulnerable, so that consumers in e-commerce transactions are in a very weak bargaining position. The importance of a country regulating legal protection for consumers is generally based on considerations of its actuality and urgency. Legal regulations for e-commerce transactions are designed to create the level of certainty needed in business transactions and to protect consumers in e-commerce transactions in order to support the growth of the digital economy in Indonesia. Current legal protection regulations for consumers in Indonesia have not been able to protect consumers in cross-border e-commerce transactions. In e-commerce transactions, there are no national borders. The consumer protection laws of each country, such as those of Indonesia, are not sufficiently helpful because e-commerce operates across borders. This type of research is normative legal research that uses statutory regulations
DOES BANK COMPETITION INCREASE OR IMPEDE SMALL BUSINESS INNOVATION? EVIDENCE FROM DEVELOPING COUNTRIES
Get PDFThe influence of bank competition on innovation has been examined in the literature, but the evidence has yielded contrasting results and has mainly focused on large or listed enterprises in a single market. This study investigates the relationship between bank competition and innovation by small businesses in less developed markets using 45,669 observations from 51 low-income and lower middle-income countries. The results indicate a positive relationship between bank competition and the likelihood of innovation. The positive association is confirmed for alternative indicators of bank competition and innovation, different econometric techniques, and alternative sample selection criteria. The results provide essential implications for small businesses and policymakers in less developed markets, including ASEAN and various geographical regions around the world.
EVALUATING BARRIERS TO INDUSTRY 4.0 ADOPTION IN ASIAN MANUFACTURING ENTERPRISES: A FUNNEL PLOT ANALYSIS APPROACH
Get PDFIndustry 4.0 (I4.0) has attracted significant attention in manufacturing fields, but its implementation success rate remains low, particularly among Asian countries facing barriers. This study synthesizes key challenges to I4.0 adoption in Asian manufacturing, drawing on funnel plot analysis and a systematic review of Scopus database entries to evaluate reliability and publication bias. The study’s validity is reinforced by a systematic review process, while its reliability is established through the rigorous application of funnel plot analysis to evaluate publication bias, thereby providing a comprehensive understanding of these barriers. Important barriers identified include a lack of technical skills, high implementation costs, limited IT literacy, concerns around data security, and unclear returns on investment (ROI), among others. These findings offer actionable insights for addressing I4.0 implementation challenges and support successful adoption across diverse manufacturing contexts in Asia. While some barriers receive less immediate attention, they act as underlying causes that trigger other, more critical barriers, creating a compound effect on I4.0 adoption. Exploring the interconnections among barriers through advanced analytical methods is crucial to uncovering their cascading effects and developing integrated strategies to address them. In addition, future research should include country-specific empirical studies to further understand regional variations and unique factors impacting I4.0 adoption
MINING CONCISE REPRESENTATIONS OF FREQUENT HIGH-UTILITY OCCUPANCY ITEMSETS USING GENERATOR PATTERNS
Get PDFA current trend in data mining is the discovery of frequent high-utility occupancy itemsets (FHUOIs) in quantitative databases. These itemsets capture user preferences and significantly contribute to transaction utility, making them valuable for real-world applications. However, analyzing the result set of all FHUOIs is complicated by its often-massive size, especially in large or dense datasets with low minimum-utility occupancy thresholds. To address this challenge, this paper introduces GFHUOI-Miner, a novel algorithm designed to efficiently extract a smaller set of all generators of FHUOIs (GFHUOIs). The algorithm reduces the search space by early elimination of non-generator FHUOI branches using a novel weak lower bound on the utility occupancy function, named pFEwlb, along with two efficient pruning strategies based on pFEwlb. Additionally, GFHUOI-Miner incorporates an optimization technique to minimize computationally expensive inclusive relationship checks among itemsets. Experimental results demonstrate that the proposed algorithm outperforms the baseline in terms of runtime, memory usage, and scalability for discovering all GFHUOIs
HYPERSPECTRAL IMAGE CLASSIFICATION ON AMULTISCALE 3D CONVOLUTIONAL NEURAL NETWORK
Get PDFIn the past decade, significant progress has been made in hyperspectral image (HSI) classification due to advances in deep learning techniques. This study introduces a novel computational framework for classifying HSIs using a multiscale 3D convolutional neural network (3DCNN). The purpose of this research is to enhance the efficiency of HSI classification by leveraging the spatial-spectral characteristics of HSI data. The methodology involves preprocessing HSI datasets, extracting features using parallel 3DCNN layers with skip connections, and evaluating performance on five benchmark datasets. Key findings demonstrate that the proposed model significantly improves classification accuracy, achieving average accuracies of 85%, 84%, 94%, 98%, and 95% on the Kennedy Space Center (KSC), Indian Pines (IP), Pavia University (PU), Pavia Centre (PC), and Botswana (BW) datasets, respectively. The originality of this study lies in the multiscale parallel design of the 3DCNN architecture, which balances computational complexity with enhanced performance. Limitations include the high computational cost associated with training deep networks, which can be mitigated by graphics processing unit (GPU) acceleration and optimized implementations
EMPLOYEE WELFARE AND STOCK PRICE CRASH RISK: EMPIRICAL EVIDENCE FROM VIETNAM
Get PDFThis study examines the impact of employee welfare on the future stock price crash risk. Using a manually collected dataset on employee welfare disclosures by firms listed on the Ho Chi Minh Stock Exchange, we find that firms with better employee welfare practices experience a lower risk of stock price crashes. This relationship is driven by the implementation of labor policies for the employees’ safety, health, and welfare. Our findings align with stakeholder theory, which suggests that enhancing employee well-being can strengthen a firm’s reputation in the eyes of stakeholders, thereby contributing to stock price stability. Moreover, managers who prioritize employee welfare may exhibit higher ethical and moral standards, making them less likely to withhold negative information. As a result, the risk of stock price crashes is mitigated. This study contributes to the existing literature by confirming the negative association between employee welfare and stock price crash risk in a frontier market where the weak institutional framework is regarded as a key driver of crash risk. The findings offer important implications for firms, investors, and policymakers
ZETA FUNCTION AND VALUE SEMIGROUP OF COMPLEX PLANE CURVE SINGULARITIES
Get PDFIn the work by A’Campo and Oka (1996), Tschirnhausen resolution towers arose as a nice tool when studying complex irreducible plane curve singularities. Using this tool combinatorially, we can revisit the extended simplified resolution graph or the toric resolution tree developed previously by the second author. We restate that the graph can help describe a resolution, namely, the monodromy and Alexander zeta functions of a complex reducible degenerate plane curve singularity. Furthermore, we show the relation between the monodromy zeta function and the value semigroup in the irreducible case, and we also give some comments on the reducible case