Good families of Drinfeld modular curves

In this paper we investigate examples of good and optimal Drinfeld modular towers of function fields. Surprisingly, the optimality of these towers has not been investigated in full detail in the literature. We also give an algorithmic approach on how to obtain explicit defining equations for some of these towers and in particular give a new explicit example of an optimal tower over a quadratic finite field

The Prominent Role of Hat Chap Cai Luong Arts in Tourist Attraction to Thoi Son Island, Tien Giang Province

The purpose of this article is to study and analyze the current development and utilization of cultural and artistic tourism products on Thoi Son Island, Tien Giang Province. The article focuses on evaluating the effectiveness of incorporating don ca tai tu music (a genre of chamber music in the traditional music of southern Vietnam) in serving tourism activities in recent times and identifying existing issues in the development process of these cultural and artistic tourism products. In addition to discussing the advantages and competitive capabilities of Thoi Son Island, the article also proposes suitable solutions for the development of cultural and artistic tourism products in the locality, particularly the application and promotion of the art of hat chap cai luong (one of the traditional theater opera plays in southern Vietnam) combined with storytelling for tourism purposes. The research methodology employed in the article combines both quantitative and qualitative approaches. The quantitative part of the research will concentrate on collecting data on tourist numbers, income from cultural and artistic tourism activities, and tourist satisfaction. The qualitative part will involve conducting interviews, surveys, and gathering opinions from experts and local residents to gain a better understanding of the issues related to cultural and artistic tourism products featuring cai luong singing on Thoi Son Island. The research findings indicate that incorporating the art of hat chap cai luong into tourism activities is effective. However, several issues have been identified that need to be addressed, such as diversifying cultural and artistic tourism products, protecting and promoting the local cultural values, and ensuring the ability to meet the future demand for cultural tourism products without causing har

Earth Pressures of Overconsolidated Collapsible Soil Subjected to Inundation

Collapsible soils are known as problematic soils, which can be found in many regions around the world. Collapsible soils possess considerable strength when they are dry; however, when they are inundated, they lose their strength and exhibit excessive settlement. The amount of soil collapse increases with the increase of the so-called collapse potential “Cp”, the wetting zone, and the degree of saturation (S). Accordingly, maximum collapse will take place due to full saturation. Collapsible soils can be inundated by heavy and continuous rainfall, excessive irrigation, broken water/sewer lines, or by rising the ground water. Furthermore, collapsible soils can be also found in construction site, in compacted fine soils at low water content (less than the optimum water content). Consequently, it is impossible to avoid construction on collapsible soils, which are potential for excessive settlement, differential settlement, landslides and falls, earth cracks. This type of soil has been responsible for damaging variety of civil engineering structures, loss of lives. Construction on such kind of soil shows extraordinary geotechnical problems, retaining walls are not an exception. With civilization, backfills behind retaining walls made of collapsible soils are widely used in practice. The earth pressures acting on these walls experience radical changes when the backfills of collapsible soils are wetted. In the literature, there are lack of theories/methods for estimating the earth pressures acting on walls retaining collapsible soils. In this study, experimental investigations on at-rest and passive earth pressures of overconsolidated collapsible soil on retaining walls were conducted.A prototype model of a vertical wall, retaining horizontal backfill of collapsible soil, was developed in the laboratory. Collapsible soil was prepared in the laboratory by mixing kaolin clay with fine sand. The model was instrumented to measure the earth pressure at strategic points on the wall, the total earth pressure acting on the wall, and the overconsolidation ratio (OCR) of the soil. Tests were conducted on the wall retaining collapsible soil at the dry and at fully saturated conditions for both the at-rest and passive earth pressures. The test results showed that both the at-rest and passive earth pressures increased with the increase of the collapse potential (Cp) and overconsolidation ratio (OCR) for the dry soil. At full saturation, the at-rest and passive earth pressures reduced considerably. Generally, the higher the collapse potential of the collapsible soil, the larger the decrease in the at-rest and passive earth pressures of the soil when the soil gets inundated. In this investigation, for the case of at-rest earth pressure, empirical formulae were developed to determine the coefficient of at-rest earth pressure (K0) of the dry and saturated overconsolidated collapsible soil. For the case of passive earth pressure, analytical model was developed. Accordingly, design theory was presented for estimating the coefficient of passive earth pressure (Kp) of overconsolidated collapsible soil at the dry and saturated conditions. Moreover, considering for the case of presence of unsaturated states of collapsible soil in practice, design charts were developed to assist designers in approximating the coefficient of at-rest (K0) and passive (Kp) earth pressures of this soil at different degree of saturation

GRAMMATICAL ERRORS IN ACADEMIC WRITING OF ENGLISH SECOND-YEAR STUDENTS

The study aimed to analyze the common grammatical errors of students in academic writing. Mixed-method research was implemented for this study. The study team gathered 110 essays from learners in the Writing Course 4 – Social Texts classroom. Then, the researchers conducted interviews with 23 learners in order to ascertain the reasons behind their grammatical errors in writing and provide suitable remedies. Participants in this research were second-year students majoring in English Studies in the Department of English Language and Culture's High-Quality Program at a Vietnamese university. The findings revealed that the errors that made up the biggest percentage of all errors were those involving the articles (25,5 %), prepositions (14,2%), and plural/singular forms (13,7 %). On the other hand, tenses (7%), passive voice (3,8%), and subject-verb agreement (1,7%) errors had the respective lowest percentages. The results of the interviews with 23 randomly selected students in this course showed that students struggled with academic writing on a number of different levels, with the root causes being a lack of vocabulary knowledge, carelessness, and uncertainty about basic grammatical structure.  Article visualizations

On asymptotic behaviors and convergence rates related to weak limiting distributions of geometric random sums

summary:Geometric random sums arise in various applied problems like physics, biology, economics, risk processes, stochastic finance, queuing theory, reliability models, regenerative models, etc. Their asymptotic behaviors with convergence rates become a big subject of interest. The main purpose of this paper is to study the asymptotic behaviors of normalized geometric random sums of independent and identically distributed random variables via Gnedenko's Transfer Theorem. Moreover, using the Zolotarev probability metric, the rates of convergence in some weak limit theorems for geometric random sums are estimated

Some firms actively use CSR to improve their image in the public media

A good image brings financial rewards, write Steven Cahan, Chen Chen, Lily Chen and Nick (Nhut H. Nguyen

Ecological Engineering and Restoration of Eroded Muddy Coasts in South East Asia: Knowledge Gaps and Recommendations

Ecological engineering (EE) was employed for developing strategies for stabilizing eroded muddy coasts (EMCs). However, there was a limited analysis of these EE strategies with respect to design, performance, and lessons learned. This study employed a critical review for addressing the limitations. There were four EE models designed with different restoration interventions for stabilizing EMCs. The models using active interventions have not been cost-effective in controlling erosion because the interventions failed to achieve their goals or were costly and unnecessary. Of the two passive intervention models, the one with structures constructed from onshore proved to be more cost-effective in terms of construction costs, the survival rate of transplanted seedlings, and levels of sea mud accumulation. Interventions with adequate consideration of the muddy coastal ecological processes and the ecological reasoning for the positioning of these interventions play a crucial role in stabilizing EMCs. A passive restoration model using gradually expanded interventions should be promoted in order to ensure sustainable management of EMCs in the future

Liquidity spillover between ETFs and their constituents

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