IMPACT OF COVID-19 PANDEMIC ON MENTAL HEALTH AND ASSOCIATED RISK FACTORS

This descriptive study provides basic data for developing a mental health promotion program by analyzing the mental health status under the impact of COVID-19 and verifying the factors affecting mental health. This study aims to identify the prevalence and associated factors of mental health after the COVID-19 pandemic. An online survey was conducted targeting a total of 156 Korean adults aged 19~64 years. Using the SPSS Win 19.0 program, the frequency, mean, t-test or ANOVA, X2-test, linear regression, and logistic regression analysis were performed. A total of 31.4%, 20.5%, and 12.8% of all subjects classified depression, anxiety, and suicidal ideation risk, respectively, and intolerance of uncertainty affected depression (β = .51) and anxiety (β = .63). In addition to intolerance of uncertainty, self-efficacy (β = -.16) was a factor affecting depression. The variables explain 35% of depression and 44% of anxiety. Further, employment status affected suicidal ideation, which increased the risk of suicidal ideation 2.71-fold with unemployed status. This paper is novel because it seeks to find that the intolerance of uncertainty was the common factor affecting mental health during COVID-19. The early detection of risk due to COVID-19 and the intolerance of uncertainty are common factors underlying mental health issues, underscoring the need for cognitive interventions at the individual level and sufficient information and psychological support related to the COVID-19 at the national level.

ROCK SLOPE SURFACE STABILITY ANALYSIS: A CASE STUDY ON HON LON ISLAND, KIEN HAI DISTRICT, KIEN GIANG PROVINCE, VIETNAM

The research aimed to study 24 rock slope surfaces along the road around Hon Lon Island, Kien Hai district, Kien Giang province, Vietnam. The analytical results have determined slope failure, wedge failure, and toppling, which occurred on almost slope surface and the average percentage of plane failure is the largest. The average percent of plane failure is 19.23%, the wedge failure is 15.35%, and the toppling fault is 6.73%. Besides, the analytical results have also identified the slope surfaces which can be the key blocks: ND-13, 18, 23, 25, 34, 37, 45, 51, 62, 63. The other analytical results show that the existence of key blocks at the rock slope surfaces in the N-S direction, dip to E at the survey locations: ND-13, 23, 63 and dip to W at the survey locations: ND-37, 45; in the NE-SW direction, dip to SE at the survey locations: ND-15, 62 and dip to NW at the survey locations: ND-18, 34; in the NW-SE direction, dip to SW at the survey location ND-51. These results have important significance to support for protecting slope surface safety.

AN INVESTIGATION TURBULENCE MODEL OF STANDARD k- TO GET OPTIMUM PARAMETERS OF TURBULENCE CONSTANTS (cµ, c1, AND c2) OF COMPRESSIBLE FLUID DYNAMICS IN A CONFINED JET

This research aims to find the optimal standard k-e turbulence model constants (cµ, c1e, and c2e) for better predicting compressible fluid dynamics in an air jet ejector. The turbulence field in a jet flow plays an important role in influencing the performance of the momentum transfer process at a shear layer in nozzle application for momentum source and mixing process. In this research, some activities have been done before analyzing and optimizing the turbulence model constants, including preliminary turbulence modeling study for compressible flow in the air-jet ejector, verification, and validation with primary experimental data as well as by other secondary data. The preliminary studies in turbulence modeling presented that the turbulence modeling of a 3mm air jet-ejector resulted in a similar trend of the relation between entrainment ratio and motive fluid pressure. The results showed that the sensitive parameters in the standard k-emodel dissipation and diffusion terms, cµ, c1e, and c2e, strongly affected the optimum value of turbulence kinetic energy (k) and dissipation rate (e), compared to the reference model. Better k and e could be obtained by changing the c2e into positively proportional, but the cµ and c1e must be changed with opposite proportionality. It was found that the optimum standard k-e model constants in the case of air-jet ejector with 3 mm nozzle diameter for cµ, c1e, and c2e are 0.05, 1.48, and 1.88, respectively, with the error values for k being -8.88% and e being -17.44%.

A NOVEL SOLAR SIMULATOR BASED ON COMBINED NATURAL-WHITE AND INFRARED LIGHT EMITTING DIODES

Despite the continuous trend of an LED solar simulator development, there was little to be found in the application of a phosphor-converted natural white LED (pc-nWLED) for construction. This article reported the design and construction of an LED solar simulator which combined a pc-nWLED with infrared LEDs. The objectives of this study are to determine the performance of a novel solar simulator including non-uniformity (SNE), temporal stability (TIE), and spectrum mismatch (SM). This is followed by an experimental study of the correlation between the LED’s temperature and SNE. A spectroradiometer, pyranometer, and a custom-made non-uniformity measurement system were applied to test the performance characteristics of this solar simulator. The results indicated that the proposed solar simulator could achieve the AAA class. The results showed 0.90-1.08 of SM, 0.83% TIE, and 1.34% of SNE. The SNE indicated the positive significant correlation with the LED’s temperature, with an approximate of +0.043% per °C. A good cooling system for the LED module was necessary to maintain constant light uniformity. The blue-chip phosphor converted white LED combination with color mixed of 730 nm, 850 nm, and 940 nm could emit a light spectrum that was very close to the reference spectrum of about 99.6%.

THE ROLE OF OVER THE TOP (OTT) SERVICE ON UTILIZATION OF TELECOMMUNICATION INFRASTRUCTURE BASED ON INDONESIAN TAX AND NON-TAX POLICY

The rapid development of Over the Top (OTT) services has enabled consumers to enjoy high service quality from technology even more. Nevertheless, OTT also brings other effects for telecommunications companies in Indonesia; namely, there are legal problems and obstacles faced regarding regulation and practice of tax and non-tax for OTT business providers because these services do not have a form of cooperation with telecommunications operators. In addition, the model of policies and regulations is still uncertain regarding how the tax and non-tax imposition should be in Indonesia. This study uses a normative juridical research method emphasizing secondary data (library research) with three legal materials, namely primary, secondary and tertiary legal materials. The research includes data searching and inventory and laws and regulations related to tax and non-tax imposition for OTT services on the utilization of telecommunication infrastructure and other relevant sources. Results of the study determine the extent to which regulations on the tax and non-tax imposition govern OTT media in Indonesia to understand and find the policy and regulatory issues related to tax and non-tax imposition practices faced by OTT business actors. In addition, it also aims to find obstacles in policy formulation and stipulation of tax and non-tax regulations for OTT business actors in Indonesia. Further, it seeks to find a tax and non-tax policies and regulations model for OTT business actors in Indonesia through a service collaboration, comparative, and normative approaches. Hence, this will also open up opportunities to increase state revenue from the imposition of tax and non-tax from all OTT service providers, both national and international.

VULNERABILITY ANALYSIS OF YELLOWFIN TUNA (THUNNUS ALBACARES) BASED ON THE SEA SURFACE TEMPERATURE DYNAMICS

The vulnerability of fisheries to climatic variability can be measured through the capacity of species to adapt to environmental change. It was also analyzed based on the analysis of fish production and susceptibility. Yellowfin tuna is one of the main commodities in the Palabuhanratu fishing port of Indonesia. The condition of yellowfin tuna fisheries needs to be studied due to the vulnerability of existing fishing activities and climate change parameters. This research was conducted at the Palabuhanratu fishing port, Sukabumi, West Java, Indonesia. Productivity and susceptibility analysis was used to determine the value of species vulnerability to fishing activities and based on the climatic variability. This study aims to analyze the vulnerability level of capture fisheries, especially for yellowfin tuna, to the Sea Surface Temperature dynamics through the analysis of productivity and susceptibility. The research will support capture fisheries management based on vulnerability analysis by providing a novel integrated analysis between productivity, susceptibility, and oceanographic data. The result of the productivity score was 2.11, and the susceptibility score was 2.17. It means that yellowfin tuna landed at the Palabuhanratu fishing port was threatened by vulnerability, but yellowfin tuna can recover and survive properly against fishing activities. The vulnerability score of yellowfin tuna was 1.6, which was classified as low vulnerability. The relationship between climate change parameters, namely sea surface temperature, and yellowfin tuna parameter, has a low-medium correlation and has an inverse relationship. Sea surface temperature can affect the development of larvae and eggs and the availability of yellowfin tuna food. By knowing the vulnerability of the yellowfin tuna fishery, sustainable fisheries management can be carried out both based on the regulation of the fishing season and the level of utilization.

MECHANICAL CHARACTERISTICS FOR COMPOSITE MATERIALS USING COMMERCIAL EPOXY RESINS AND DIFFERENT FILLERS

Epoxy resins are thermoset polymers that consist of epoxide groups in their molecular structure. It shows many attractive characteristics like strong adhesion, excellent mechanical strength, low shrinkage, excellent insulator, excellent chemical stability for acidic and basic environments, and microbial resistance due to the presence of hydroxyl groups and ether bonds and its three-dimensional structure. Many of these characteristics can be modified by adding strong bindings in the polymeric chain to give more improved characteristics. This research aims to prepare a composite material using epoxy resin and different types of fillers to achieve resistance to high kinetic energy impact. Experimental work is focused on preparing cured epoxy resin samples by using diglycidyl ether of bisphenol A (DGEBA) resin with tertiary amine as a hardener. In order to obtain different samples with different properties, we add different types of fillers, then mechanical tests are used to measure the mechanical properties of the samples. The results have proved that fiberglass is the best filler added to epoxy resins to improve its mechanical properties.

STUDENTS’ READINESS FOR E-LEARNING: A CASE STUDY OF STUDENTS IN HIGHER EDUCATION

The process of e-learning is the operations that involve humans, computers, the Internet, and instructional material and produce the outputs to learners and the organization. This research aimed to study students' readiness for e-learning of graduate students in IAIN Kendari, Indonesia. The research sample consisted of 168 graduate students who were selected purposively. The questionnaire was adapted from Watkins and interviewing 10% of the sample group was conducted to collect the data. The research findings showed that the students were ready for the e-learning, as shown by the overall mean score is 3.72, which is above Mo = 3.40. Due to the low means of statistical calculation, three important items need to be improved, such as Students' household distraction reduction, students' comfort to be involved in multiple online discussions, and students' ability to take notes during online discussions, should be considered. Based on the interview, some challenges met during online learning that reduced students' readiness were unstable internet connection, lecturer's presence on screen, inconducive learning environment, and inability to be a multitasker. Hence, it is recommended that the university and students discuss to improve students' readiness in motivation and technology access.

MISUSE OF TOPICAL CREAMS AIMED AT PREVENTING AND TREATING MELASMA AND FRECKLES AMONG WORKING WOMEN

Topical creams used to treat and prevent melasma and freckles contain corticosteroids, hydroquinone, mercury, and retinoic to lighten skin color. Misuse of these products and the rate of adverse effects have increased greatly in recent years. This study aims to assess the misuse of topical cream to prevent and treat melasma and freckles among working women in northeast Thailand. Our population consisted of 1,143 working women in the region aged 30-59 years old. The respondents were recruited from four provinces eight districts using a structured questionnaire distributed via a multi-stage random sampling method. Descriptive statistics and logistic regression were used to represent and analyze the data. Eight hundred sixty-two (75.42%) of the respondents were users, and 105 (12.18%) had misused the products. The prevalence of misuse of products containing mercury, steroids, hydroquinone, retinoic acid, and mercury plus retinoic acid was 43.8%, 11.43%, 15.24%, 12.38%, and 17.15%, respectively. Factors associated with misuse of this product were age 30-44 years, education level less than a bachelor’s degree, working as a housekeeper or freelancer, presence of melasma and freckles, average monthly income ≤ 15,000 THB and low levels of knowledge and health literacy. Misuse of medication to treat pigmentary disorders is a growing public health concern. Social media and nonprofit campaigns should be implemented to create awareness of these products' misuse and adverse effects.

SPATIAL ASSOCIATION PATTERNS OF SMOKING, TOBACCO OUTLET DENSITY, AND SECONDHAND SMOKE IN THAILAND

Thailand has a higher prevalence of smoking behaviors which puts people at risk of morbidity and mortality. This study aimed to determine the spatial association of smoking behaviors and their associated factors among the population of Thailand. This study was conducted using a data set from the National Statistical Office of Thailand, 2017. A Moran’s I, local indicators of spatial association (LISA), and spatial regression were used to identify the spatial autocorrelation between tobacco outlet density, the prevalence of secondhand smoke, and smoking behaviors among Thai people. According to the results, among 88,689 participants, the prevalence of smoking behaviors was 18.00 per 1,000 population. There was global spatial autocorrelation between tobacco outlet density, the prevalence of secondhand smoke, and smoking behaviors with the Moran’s I values of 0.120 and 0.375, respectively. The LISA analysis identified significant positive spatial local autocorrelation of smoking behaviors in the form of nine high-high clusters of tobacco outlets density and ten high-high prevalence clusters of secondhand smoke. The prevalence of secondhand smoke predicted smoking behaviors by 62.8 percent. There were spatial associations between tobacco outlet density and secondhand smoke problems that led the youngsters to start smoking. It is a general recommendation to strictly enforce policies and laws to control smoking, and cover all regions in Thailand.