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The Inception of Ideas: How Students Use ChatGPT for Academic Writing
Get PDFThis study investigated the experiences of students who have used ChatGPT for writing assistance. A survey was conducted to collect data on students' usage frequency, preferences, and perceptions of ChatGPT's suggestions for improving their writing. The survey also explored if students encountered any technical issues while using ChatGPT and whether they found it helpful in overcoming writer's block or not. Results showed students preferred ChatGPT over other writing tools and found its suggestions helpful and accurate. Most students felt that ChatGPT was equally helpful across different types of writing. Although some technical issues were reported, they were relatively minor. Overall, students reported increased confidence in their writing abilities after using ChatGPT and would recommend it to other students. Incorporating ChatGPT into the writing process may help students overcome writer's block and improve their writing habits. This study suggests that ChatGPT is a useful tool for students who require writing assistance, and its suggestions are perceived as helpful and accurate
A A COMPARATIVE REVIEW AND NOVEL DESIGN POSSIBILITIES ON SOLAR-DRIVEN ABSORPTION LIBR-H2O REFRIGERATION SYSTEM
No full textSolar energy is a promising source of energy because of its potential due to the reduction usage of non-renewable energy. As the demand for cooling increases, solar-powered cooling technologies are becoming increasingly promising. Among the different solar cooling systems, LiBr-H2O absorption chillers are commonly used due to their advantages over NH3-H2O systems. Multiple cycle LiBr-H2O chillers can be powered by easily available flat-plate, evacuated tubular or parabolic solar collectors. This paper reviews Theoretical Principles-Based Analysis and Simulations of solar LiBr-H2O absorption cooling systems, performance comparison of each types and introduces new design options related to auxiliary energy systems and cooling mode cycle. The paper also summarizes other main types of solar absorption cooling systems, including double-effect, half-effect, triple effect and give updates of new technology design of hybrid effect. The choice of water-cooled or air-cooled absorption refrigeration depends on the local climate and water availability. Recent advances have made air-cooled absorption refrigeration a viable option, with comparable COP to water-cooled systems and lower maintenance requirements. Additionally, geothermal heat rejection with low pressure drops can further reduce energy consumption. Solar-powered double-effect absorption cooling systems are recommended for buildings with high cooling loads, while half-effect are suitable for air-cooled solar absorption cooling systems in hot and dry regions with limited water. This paper is specifically intended for those interested in developing solar-driven LiBr-H2O absorption chillers, emphasizing the importance of establishing standardized design guidelines to specific regions and climates in order to promote and expand the usage of solar cooling systems.Solar energy emerges as a promising renewable resource to mitigate reliance on non-renewable energy sources, especially in addressing the escalating demand for cooling. LiBr-H2O absorption chillers, preferred over NH3-H2O systems, are widely employed in solar cooling technologies, driven by flat-plate, evacuated tubular, or parabolic solar collectors. This paper presents a Theoretical Principles-Based Analysis and Simulations of solar LiBr-H2O absorption cooling systems, conducting a comprehensive performance comparison, and introducing innovative design options for auxiliary energy systems and cooling mode cycles. Furthermore, it delves into various solar absorption cooling systems, including double-effect, half-effect, and triple effect, providing updates on hybrid effect technology. The choice between water-cooled and air-cooled absorption refrigeration hinges on local climate and water availability. Recent advancements have positioned air-cooled absorption refrigeration as a viable alternative, demonstrating comparable Coefficient of Performance (COP) to water-cooled systems with reduced maintenance requirements. Incorporating geothermal heat rejection with low pressure drops further augments energy efficiency. Recommendations advocate solar-powered double-effect absorption cooling systems for structures with high cooling loads and half-effect systems for air-cooled applications in arid regions. The paper underscores the imperative of standardized design guidelines tailored to specific regional and climatic considerations, facilitating the widespread integration of solar cooling systems
Deterministic Double Dose Vaccination Model of COVID-19 Transmission Dynamics - Optimal Control Strategies with Cost-Effectiveness Analysis
Get PDFIn this study, we propose a deterministic double dose vaccination model of COVID-19 transmission dynamics optimal control with cost-effectiveness analysis. It is imperative for decision-makers and the government to prioritize the application of preventive and control measures for COVID-19 based on efficiency and costbenefit analysis. This is pivotal in resource-constrained regions where the disease is endemic. Thus, this work is mainly devoted with the development and analysis of an optimal control for COVID-19 dynamics with five timevarying functions; first dose vaccination, second dose vaccination, personal protection, testing or screening, and treatment. The model is qualitatively analysed with the overall goal to minimize the spread of COVID-19 and the costs related to control implementation with the aid of optimal control theory. The effect of adopting each control intervention in each of the three distinct groups which are created by classifying all conceivable combinations of at least three control interventions is demonstrated through the numerical simulations of the optimality system. Using the average cost-effectiveness ratio and incremental cost-effectiveness ratio techniques, the most economical control intervention is determined for each group. The study reveals that when the resources are readily available, application of the strategy that combines optimal first dose vaccination, personal protection, screening or testing and treatment is as efficient as implementing all the five optimal control interventions simultaneously as they both avert the same number of infections. However, in resource-limited communities when joint implementation of only three interventions is possible, the strategy combining personal protection, testing or screening and treatment is strongly recommended. Out of all the intervention options being considered, this strategy is also affirmed to be the most cost-effective overall. Economic evaluation of the control intervention strategies further suggests that combination of first dose vaccination, second dose vaccination, testing or screening and treatment is the most cost-effective strategy when implementation of only four interventions is strictly allowed
Optimal Control Analysis in the Treatment of Solid Tumors using Combined Therapy
Get PDFIn this paper, we develop and analyze a mathematical model that describes the dynamic interactions and competitions among tumor cells, normal cells, immune cells, and transforming growth factor-beta within the tumor microenvironment. We conducted qualitative analyses to examine the persistence or extinction of each cell population and analyzed the regions of stability and instability across various equilibria. Additionally, we formulated and solved an optimal control problem using the Pontryagin’s maximum principle, aiming to minimize tumor size and the concentration of transforming growth factor-beta while also reducing chemotherapy and siRNA drug-induced toxicity in patients. Numerical simulations are performed for the model with and without treatment. We demonstrate scenarios where neither individual treatment is capable of reducing both tumor and TGF-β, but their combination achieves a substantial reduction
MODIFIKASI KOEFISIEN RESPON SEISMIK (CS) UNTUK PERANCANGAN BANGUNAN SUPER TINGGI MENGGUNAKAN METODE PERFORMANCE-BASED DESIGN
No full textAbstract
Performance-Based Design (PBD) method is widely used to design or evaluate super high-rise building against earthquake loads. The building is expected to present a certain level of performance set on FEMA 303 in response to ground motions, and should meet the target performance at Service Level Earthquake (SLE) and at Risk-Targeted Maximum Considered Earthquake (MCER). The performance level would be determined by using non-linear time history analysis and it requires non-linier parameter based on reinforcement of the structural elements. The common method proposed by Tall Building Initiative (TBI) requires the structural members are designed using response spectra at Service Level Earthquake (SLE). The problem is the ground motion and response spectra at Service Level Earthquake (SLE) are not always immediately available. In this paper, the modified seismic response coefficient (CS-M) is introduced in designing the structural members, as an initial step of Performance-Based Design (PBD), using the common response spectra of Risk-Targeted Maximum Considered Earthquake (MCER) instead of Service Level Earthquake (SLE). The performance of buildings is evaluated at Service Level Earthquake (SLE) and Risk-Targeted Maximum Considered Earthquake (MCER) to validate that design with modified seismic response coefficient (CS-M) is still in accordance with method by Tall Building Initiative (TBI).
Keywords: Modified Seismic Response Coefficient (CS-M), Performance-Based Design (PBD), Risk-Targeted Maximum Considered Earthquake (MCER), Service-Level Earthquake (SLE), Tall Building Initiative (TBI).
Abstrak
Metode Desain Berbasis Kinerja (PBD) banyak digunakan untuk merancang atau mengevaluasi bangunan super tinggi terhadap beban gempa bumi. Bangunan diharapkan dapat mencapai tingkat kinerja tertentu yang ditetapkan dalam FEMA 303 sebagai respons terhadap gerakan tanah, dan harus memenuhi kinerja target pada Service Level Earthquake (SLE) dan pada Risk-Targeted Maximum Considered Earthquake (MCER). Tingkat kinerja akan ditentukan dengan menggunakan analisis riwayat waktu non-linier dan membutuhkan parameter non-linier berdasarkan penulangan elemen struktural. Metode umum yang diusulkan oleh Tall Building Initiative (TBI) mengharuskan komponen struktural dirancang menggunakan respons spektra pada Service Level Earthquake (SLE). Masalahnya adalah gerakan tanah dan respons spektra pada Service Level Earthquake (SLE) tidak selalu tersedia secara langsung. Dalam paper ini, diperkenalkan koefisien respons seismik yang dimodifikasi (CS-M) dalam merancang komponen struktural, sebagai langkah awal Desain Berbasis Kinerja (PBD), dengan menggunakan respons spektra umum dari Risk-Targeted Maximum Considered Earthquake (MCER) sebagai ganti dari Service Level Earthquake (SLE). Kinerja bangunan dievaluasi pada kondisi Service Level Earthquake (SLE) dan Risk-Targeted Maximum Considered Earthquake (MCER) untuk memvalidasi bahwa desain dengan koefisien respons seismik yang dimodifikasi (CS-M) masih sesuai dengan metode yang diajukan oleh Tall Building Initiative (TBI).
Kata kunci: Koefisien Respons Seismik yang Dimodifikasi (CS-M), Desain Berbasis Kinerja (PBD), Risk-Targeted Maximum Considered Earthquake (MCER), Service-Level Earthquake (SLE), Tall Building Initiative (TBI)
Perbandingan Specific Refining Energy pada Mesin Refiner Jenis Double Disk dengan Conical: Studi Kasus pada Pembuatan Kertas Tulis Cetak
Get PDFThe refining process is a part of the paper-making process that requires a large amount of energy. The strategy used is to change the type of refiner machine from Conical to Double Disc Refiner (DDR) because DDR spends less energy. At a consistent range of 4% Specific Edge Load (SEL) DDR is 1.4–4 J/m while conical SEL is 0.9–6.0 J/m. This research will test the energy used in making HVS paper 80-gram by referring to what has been mentioned. The consistency used is in the range of 4.4–4.6%. As supporting parameters, the physical properties of HVS 80-gram paper were used, namely bulk, tearing, tensile, and bursting. Energy and physical properties were measured for 28 days with 6 samplings per day. The comparison was carried out on days 10 to 26 because there was incomplete data on DDR on days 7–9 and day 27. The results of this study showed that the type replacement from conical to DDR was at 1.52%. The physical property of the paper that experienced a significant change was the paper porosity, which was 28.58%.Proses refining adalah bagian dari proses pembuatan kertas yang membutuhkan energi yang besar. Strategi yang digunakan adalah mengganti jenis mesin refiner dari Conical ke Double Disc Refiner (DDR) karena dari sisi energi, DDR memiliki energi yang lebih rendah. Pada konsisten di kisaran 4% Specific Edge Load (SEL) DDR adalah 1.4- 4 J/m sedangkan SEL conical adalah 0.9–6.0 J/m. Dengan latar tersebut, penelitian ini bertujuan akan menguji energi yang digunakan pada pembuatan kertas HVS 80 gram. Konsistensi yang digunakan adalah di kisaran 4.4–4.6%. Sebagai parameter pendukung digunakan uji sifat fisik kertas HVS 80 gram yaitu bulk, tearing, tensile dan bursting. Pengukuran energi dan sifat fisik dilakukan selama 28 hari dengan 6 kali pengambilan per harinya. Untuk membandingkan dilakukan pada hari ke 10 hingga ke 26 karena ada kekosongan ketidaklengkapan data pada DDR pada hari ke 7-9 dan hari ke 27. Hasil dari penelitian ini menunjukkan bahwa penggantian jenis dari conical ke DDR berada di angka 1.52%. Sifat fisik kertas yang mengalami perubahan signifikan adalah porosity kertas yaitu sebesar 28.58%
Dukungan Orang Tua dan Motivasi Berprestasi Anak Usia Muda dalam Olahraga: Sebuah Studi Korelasi dalam Cabang Olahraga Renang
Get PDFParental support in the development of achievement is one of the crucial factors, especially for young children, as it can influence the development of their skills to achieve high performance. Parental involvement in supporting their child's achievement impacts various aspects, such as motivation, which is generally considered to involve the initiation, direction, intensity, and persistence of individual behavior, and also positively affects the child's confidence and independence in training. This study aims to examine the relationship between parental support and achievement motivation in young children in the sport of swimming. This research employs a quantitative descriptive method with a correlational research design. The population in this study consists of 17 swimming athletes from Delta Valley Cimahi, all of whom were included as the research sample. The research instrument used two questionnaires, each consisting of 36 items regarding parental support and 30 items regarding achievement motivation, completed by the athletes via Google Forms using a Likert scale as the response option. The data was processed and analyzed using the Spearman rank correlation test in SPSS Version 25. The results showed that parental support has a significant correlation with achievement motivation in young children in the sport of swimming. Therefore, it can be concluded that good parental support will lead to higher achievement motivation in young children in the sport of swimming.Dukungan orang tua dalam pembinaan prestasi merupakan salah satu faktor penting khususnya bagi anak usia muda, yang dapat mempengaruhi perkembangan keterampilannya untuk meraih prestasi yang tinggi. Keterlibatan orang tua dalam mendukung prestasi anaknya mempunyai pengaruh dalam berbagai aspek, seperti motivasi yang umumnya dianggap melibatkan permulaan, arah, intensitas, dan ketekunan perilaku individu, serta memberikan dampak positif pada kepercayaan diri dan kemandirian anak dalam berlatih. Peneliti bertujuan untuk mengkaji hubungan antara dukungan orang tua dengan motivasi berprestasi anak usia muda dalam cabang olahraga renang. Penelitian ini menerapkan metode deskriptif kuantitatif dengan desain penelitian korelasional. Dalam penelitian ini populasi terdiri dari atlet renang Delta Valley Cimahi yang berjumlah 17 atlet yang kemudian seluruhnya menjadi sampel penelitian. Instrumen penelitian menggunakan dua kuesioner yang masing-masing terdiri dari 36 item tentang dukungan orang tua dan 30 item tentang motivasi berprestasi, dan diisi oleh atlet melalui google form dengan menggunakan skala likert sebagai opsi pilihan jawaban. Data diolah dan dianalisis menggunakan uji korelasi rank spearman pada SPSS Versi 25. Hasil penelitian menunjukkan bahwa dukungan orang tua memiliki korelasi yang signifikan dengan motivasi berprestasi anak usia muda dalam cabang olahraga renang. Maka dapat disimpulkan bahwa dukungan orang tua yang baik akan membuat anak usia muda semakin memiliki motivasi berprestasi yang lebih tinggi dalam cabang olahraga renang
DAMPAK KEBIJAKAN VISA ON ARRIVAL (VOA) DAN BEBAS VISA KUNJUNGAN (BVK) TERHADAP ASPEK SOSIAL-BUDAYA INDONESIA
Get PDFThe Indonesian government has implemented Visa on Arrival (VoA) and Visa-Free Visit (BVK) policies. These facilities make it easier for prospective international tourists to explore Indonesia and can have both positive and negative impacts within its scope. This research is depicted through phenomena using a qualitative descriptive design and data collection through reports, news, and other supporting documents via literature study. The interaction between international tourists and local communities can lead to friction resulting in criminal acts. This can undermine Indonesia's resilience and security in socio-cultural aspects. Many criminal acts have been committed by international tourists, including an incident where a female foreign national disrupted a traditional Balinese dance performance and was not wearing clothing.Pemerintah Indonesia telah menerapkan kebijakan VoA dan BVK. Fasilitas ini memudahkan para calon wisatawan mancanegara untuk mengeksplor Indonesia dan dapat memberikan dampak pada ruang lingkupnya, baik secara positif maupun negatif. Penelitian ini digambarkan melalui fenomena dengan desain deskriptif kualitatif dan pengumpulan data melalui laporan, berita, dan dokumen pendukung lain melalui studi pustaka. Interaksi antara wisatawan mancanegara dengan masyarakat lokal memungkinkan terjadinya gesekan yang menimbulkan tindak kriminal. Hal ini dapat merusak ketahanan dan keamanan Indonesia terhadap aspek sosial budaya. Banyak terjadi tindak kriminal yang dilakukan oleh wisatawan mancanegara, salah satunya, WNA perempuan menerobos pagelaran tarian tradisional Bali dan tidak mengenakan busana
Business Model Canvas (BMC) Approach for Ecotourism Development Based on Islamic Boarding School Community (Case: Cipeujeuh Valley, Darul Arqam Muhammadiyah Islamic Boarding School)
Get PDFThis study investigates the potential for ecotourism in Cipeujeuh Valley, which is situated near the Darul Arqam Muhammadiyah Islamic boarding school in Garut Regency. The research examines the factors that drive tourists to visit the area, the level of community engagement, and the development of a community-based ecotourism business model. The data was gathered using descriptive statistics, the Ecotourism Opportunity Spectrum (ECOS) framework, and rapid rural appraisal techniques. The results indicate that Cipeujeuh Valley has intermediate ecotourism spectrum, with push factors such as sports and adventure, recreation and relaxation, social status, and quality time, and pull factors including nature and the local community, and enjoying facilities. The community is generally receptive to ecotourism development, with 61.3% expressing interest and 38.7% not. The study suggests that educational institutions, communities, organizations, and families can be targeted through a business model canvas that offers unique environments, sustainable resource use, community empowerment, educational tourism, and economic development. Key resources include natural attractions, religious and local wisdom activities, infrastructure, and a skilled workforce, while key activities involve nature-based and community-based tourism experiences.
Membawa Tempat-tempat dalam Cerita ke Kehidupan Nyata: Pengaruh Cerita Masa Kecil terhadap Niat Berkunjung ke Tempat-tempat dalam Cerita
No full textThis paper presents a study that aims at investigating relationship between childhood stories and intention to visit the places in the stories. It involved 145 Tourism college students in Indonesia who rated their answers to 17 statements on an e-questionnaire using a 5-point Likert scale. Findings of the study showed there is a significant relationship between childhood stories and intention to visit. However, despite respondents’ interest in visiting the places in their childhood stories, they still would consider visiting other places beyond the places in their childhood stories provided they have other options. The findings can contribute to the knowledge about the relationship between childhood experiences and adults’ attitudinal and behavioral patterns, and to the planning, development, and marketing for a specific tourist market segment. Future studies can consider exploring the 54.5% of unknown factors affecting respondents’ interest in visiting tourist destinations or attractions associated or related to their childhood stories, as well as the volume of this specific tourist market segment.Paper ini mempresentasikan sebuah studi yang bertujuan untuk melihat hubungan antara cerita masa kanak-kanak dan niat berkunjung ke tempat-tempat yang diceritakan dalam cerita-cerita tersebut. Studi ini melibatkan 145 mahasiswa Kepariwisataan di Indonesia yang memberikan nilai pada jawaban mereka di kuesioner daring yang menggunakan skala Likert 5-point. Temuan studi menunjukkan adanya hubungan yang signifikan antara cerita masa kanak-kanak dengan niat berkunjung. Akan tetapi, walaupun responden tertarik berkunjung ke tempat-tempat dalam cerita masa kanak-kanak mereka, mereka masih akan mempertimbangkan tempat-tempat lain di luar temapt-tempat dalam cerita masa kanak-kanak mereka apabila mereka memiliki pilihan lain. Temuan studi dapat berkontribusi pada pengetahuan tentang hubungan antara pengalaman masa kanak-kanak dengan pola sikap dan perilaku orang dewasa, dan begi perencanaan, pengembangan, dan pemasaran bagi satu segmen pasar wisatawan tertentu. Studi di masa mendatang dapat mempertimbangkan mengeksplor 54,5% faktor-faktor yang tidak diketahui yang memengaruhi minat responden berkunjung ke destinasi atau daya tarik wisata yang dihubungkan atau terkait dengan cerita masa kanak-kanak mereka, juga besaran segmen pasar wisatawan khusus