Internet Addiction and Online Gaming Disorder in Children and Adolescents During COVID-19 Pandemic: A Systematic Review

Patria Yudha Putra(Patria Yudha Putra ),Izzatul Fithriyah(Izzatul Fithriyah ),Zulfa Zahra(Zulfa Zahra ) 대한신경정신의학회 2023 PSYCHIATRY INVESTIGATION Vol.20 No.3

The Indonesian government has enforced several social restrictions to prevent the spread of the coronavirus disease-2019 (COVID-19) virus, such as closures of in-person schools, public areas, and playgrounds as well as reduced outdoor activities. These restrictions will affect mental health of school-age children and adolescents. The internet is chosen as one of the media to keep academic activities running, but excessive internet use will increase internet addiction and online gaming disorder. This study aimed to understand the prevalence and psychological impacts of internet addiction and online gaming disorder on children and adolescents globally during the pandemic. Systematic searches were carried out on the PubMed, ProQuest, and Google Scholar search engines. All studies were assessed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 criteria and the Newcastle Ottawa Scale. Five studies met the criteria for assessing internet addiction and online gaming disorder cases in children and adolescents. Four studies discussed internet addiction, and one study addressed the negative impacts of online gaming on children and adolescents during the COVID-19 pandemic. There has been an increase in internet use and online gaming disruption in children and adolescents in almost all parts of Asian and Australian countries during the COVID-19 pandemic period.

Analysis of Indonesian Tuna Fish Export to Twelve Main Destination Countries: A Panel Gravity Model

Wayan Edy Darma PUTRA(Wayan Edy Darma PUTRA ),NASRUDIN(NASRUDIN ) 한국유통과학회 2023 Asian Journal of Business Environment (AJBE) Vol.13 No.1

Purpose: This study purposes to analyze the determinants of the volume of Indonesian tuna exports. Research design, data and methodology: The framework was developed from the gravity model for trade, which was expanded with additional variables of competitiveness, exchange rate, and industrial share of the destination country. The data sources used in this study are UN Comtrade and the World Bank. The data used is yearly data from 12 countries in 2001-2019. The scope of the study is limited to exports to the twelve main export destinations. Panel data regression analysis is used to determine the factors that affect the volume of Indonesian tuna exports. Results: The results show that according to the theory, Indonesia's GDP has a positive effect and economic distance has a negative effect on the volume of the exports. Meanwhile, the GDPs of the destination countries are not proven to have a positive effect. However, the higher the industrial share in the country, the higher the export volume tends to be. Conclusions: The conclusion obtained from this study is that Indonesia's GDP, economic distance, real exchange rate, industrial GDP share of the destination country, and the RCA index affect the volume of Indonesian tuna exports.

Experimental and numerical study on the high-speed ship hydrodynamics influenced by an interceptor with varied angle of attack

Putra Arfis Maydino Firmansyah,Suzuki Hiroyoshi 대한조선학회 2024 International Journal of Naval Architecture and Oc Vol.16 No.-

Efforts to improve the hydrodynamic performance of high-speed ships have been underway for a long time. There are different approaches, one of which is to take advantage of an interceptor. Conventionally, the interceptor blades are mounted vertically on the ship’s bottom transom, oriented at a zero-degree angle of attack (AoA). This study comprehensively explores high-speed ships’ hulls with and without interceptor configurations, encompassing both negative and positive AoA of the interceptor, conducted through experimental and numerical methods using a fully captive model. The interceptors are strategically positioned and configured. Each configuration was examined under varying AoA settings, with uniform interceptor depths and systematic trim angle adjustments. The Computational Fluid Dynamics (CFD) approach simulates the local flow dynamics around the hull, thoroughly analyzing resistance, pressure distribution, lift force, wave profile, and trim moment. The results indicate that interceptor placement near the keel with AoA adjustments significantly reduces hydrodynamic resistance, while AoA changes have limited impact in other positions. Lift force analysis shows interceptors improve lift compared to the bare hull, but this improvement is not linear across positions. Furthermore, it is observed that adjustments in AoA influence lift, with a negative AoA generally being considered favorable. In summary, carefully considering placement, AoA, and height-to-length ratio is necessary to maximize interceptor advantages.

Interface modification of tempered martensite utilizing nano-scale transition carbide via isothermal sub-zero treatment

Putra, D.P.,Widiantara, I.P.,Yang, H.W.,Kamil, M.P.,Fatimah, S.,Mahendradhany, A.P.,Park, K.S.,Ko, Y.G. Elsevier 2018 Materials letters Vol.231 No.-

<P><B>Abstract</B></P> <P>The present study investigated the influence of isothermal holding time on characteristics of nano-scale transition carbide and interfaces of tempered high-carbon martensitic steel processed by sub-zero treatment (SZT). We interpreted a stress-induced activity of carbon atoms through SZT prior to tempering, which was crucial for obtaining desirable precipitation of transition carbide. The modification upon interfaces under the influence of transition carbide characteristics was recognized for the first time and discussed based on mechanism of precipitate-interface interaction in relation to the nanohardness value.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Effect of isothermal SZT were investigated. </LI> <LI> Cold stress relaxation was crucial for obtaining desirable η-carbide characteristics. </LI> <LI> Interface modification via pinning effect of η-carbide improved nanohardness. </LI> </UL> </P>

Environmental Performance and Earnings Persistence: Empirical Evidence from Indonesia

PUTRA, Ferdy Korea Distribution Science Association 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.3

When firms have higher environmental performance, they can provide sustainable business that allows firms to build the value of credibility and ethics, higher reputation, higher productivity, and lower costs. The advantages of environmental responsibilities help firms to maintain their earnings level over a long-term period. This research aims to examine the effect of environmental performance on earnings persistence. Research samples include 413 manufacturing firms-years listed in the Indonesian Stock Exchange and the PROPER evaluation in 2013-2019. Environmental performance is measured by PROPER evaluation rating. The result shows that environmental performance has a positive effect on earnings persistence. The advantage of environmental responsibilities allows firms to enjoy performance sustainability and persistence in a long-term period, not only periodically. Also, the positive effect of environmental performance on earnings persistence occurs more in the environmentally sensitive industry than non-sensitive ones. Since an environmentally-sensitive industry brings more environmental damage, higher environmental performance is more valuable to provide sustainability. This research has limitations to use all the Indonesian Stock Exchange-listed firms since not all firms participate in the PROPER evaluation. This research implies firms' management should maintain earnings persistence and sustainability by implementing higher-quality environmental responsibility, especially for firms in an environmentally-sensitive industry.

The Impact of Quality and Price on the Loyalty of Electronic Money Users: Empirical Evidence from Indonesia

PUTRA, Pratama,JAYADI, Riyanto,STEVEN, Ignatius Korea Distribution Science Association 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.3

The electronic money market in Indonesia continues to experience an increase in the number of users and volume of transactions. However, the electronic money market, especially server-based, in Indonesia is becoming concentrated into a few issuers. Electronic money issuers compete in price and promotion wars to gain new customers and maintain their existing ones. This paper presents an analysis of the orientation and factors that influence the loyalty in electronic money products. The research model variables in this study are adopted from the E-Service Quality and Marketing Mix categories. These variables are hypothesized to affect the perceived value and then customer loyalty. The research population consists of all Indonesians who use server-based electronic money, with a sample of 400 individuals. The results show that, in the E-Service Quality group, reliability, responsiveness, and security significantly affect perceived value, while the perceived price and perceived promotional benefits significantly affect perceived value in the Marketing Mix group. The perceived price has the highest effect on the perceived value and customer loyalty, while the perceived value has a significant effect on customer loyalty. Finally, it was found that the customer is more sensitive to the price than quality in using electronic money.

Effects of button color and background on augmented reality interfaces

Putra Yamin(야민 푸트라),Jaehyun Park(박재현) 대한인간공학회 2021 대한인간공학회 학술대회논문집 Vol.2021 No.11

Objective: The aim of this study is to understand the usability of common button color and background choices used in the existing augmented reality (AR) interface. Background: AR technologies are becoming increasingly popular. AR is increasingly used in dynamic situations, such as when driving using an AR head-up display. However, studies regarding the usability of AR interfaces, especially about the colors, are scarce. Method: 24 participants performed button selection tasks in an experiment using Microsoft HoloLens. The task completion time was measured along with a subjective satisfaction and simulator sickness score. Results and Conclusion: The results showed that there was a significant difference in completion time between black, grey, and dynamic backgrounds. Furthermore, the black background required a significantly shorter task completion time than the grey and dynamic background. There was a significant difference in completion time between the colors orange and blue and between white and blue. On a dynamic background, the most effective button color to choose is orange, and the least effective button color is blue. Application: The results of this study can be used for color choices in designing AR applications and devices.

Structural optimization of stiffener layout for stiffened plate using hybrid GA

Putra, Gerry Liston,Kitamura, Mitsuru,Takezawa, Akihiro The Society of Naval Architects of Korea 2019 International Journal of Naval Architecture and Oc Vol.11 No.2

The current trend in shipyard industry is to reduce the weight of ships to support the reduction of CO₂ emissions. In this study, the stiffened plate was optimized that is used for building most of the ship-structure. Further, this study proposed the hybrid Genetic Algorithm (GA) technique, which combines a genetic algorithm and subsequent optimization methods. The design variables included the number and type of stiffeners, stiffener spacing, and plate thickness. The number and type of stiffeners are discrete design variables that were optimized using the genetic algorithm. The stiffener spacing and plate thickness are continuous design variables that were determined by subsequent optimization. The plate deformation was classified into global and local displacement, resulting in accurate estimations of the maximum displacement. The optimization result showed that the proposed hybrid GA is effective for obtaining optimal solutions, for all the design variables.

The use of computer vision to estimate tree diameter and circumference in homogeneous and production forests using a non-contact method

Putra Bayu Taruna Widjaja,Ramadhani Nadira Janna,Soedibyo Dedy Wirawan,Marhaenanto Bambang,Indarto Indarto,Yualianto Yualianto 한국산림과학회 2021 Forest Science And Technology Vol.17 No.1

Tree diameter and circumference measurements are important metrics that should be monitored periodically and which can be used to determine rates of plant growth, timber production (wood), rubber tapping time, and to estimate the nutrient content of the soil in agroforestry especially for rubber and Albizia sp. trees. In this study, we evaluated the use of optical sensors, including a smartphone camera, which were analyzed by an image processing technology to estimate tree circumference of homogeneous and production forests especially rubber and Albizia forest plantations, through a real-time tree diameter measurement approach. Camera measurements were carried out for the diameter at breast height (DBH) and a certain distance of each tree (with the diameter of tree range of 6–50 cm). The results show that the use of smartphone camera measurements is highly correlated with manual measurements obtained using a tree caliper or meter tape in estimating tree circumference with coefficient of determination (R2) and RMSE of 0.95 and 7.9 cm, respectively. Thus, this tool can be employed as an alternative method for measuring tree diameter and circumference. Tree diameter and circumference measurements are important metrics that should be monitored periodically and which can be used to determine rates of plant growth, timber production (wood), rubber tapping time, and to estimate the nutrient content of the soil in agroforestry especially for rubber and Albizia sp. trees. In this study, we evaluated the use of optical sensors, including a smartphone camera, which were analyzed by an image processing technology to estimate tree circumference of homogeneous and production forests especially rubber and Albizia forest plantations, through a real-time tree diameter measurement approach. Camera measurements were carried out for the diameter at breast height (DBH) and a certain distance of each tree (with the diameter of tree range of 6–50 cm). The results show that the use of smartphone camera measurements is highly correlated with manual measurements obtained using a tree caliper or meter tape in estimating tree circumference with coefficient of determination (R2) and RMSE of 0.95 and 7.9 cm, respectively. Thus, this tool can be employed as an alternative method for measuring tree diameter and circumference.

Analysis of Characteristics and Components of In-Vehicle AR-HUD Interface

Putra Yamin(야민 푸트라),Jaehyun Park(박재현) 대한인간공학회 2021 대한인간공학회 학술대회논문집 Vol.2021 No.6