ITB Journal
Not a member yet
5999 research outputs found
Sort by
Penta- and Tetra-cyclic Triterpenoids from Aglaia cucullata Stembark and Cytotoxicity against Cancer and Normal Cells
Full text linkThree triterpenoid compounds, belonging to the penta- and tetracyclic groups, were successively isolated from the stembark of Aglaia cucullata and identified as b-amyron (1), dammaradienon (2), and cabralealactone (3). After extensive extraction, chromatographic separation and purification, compounds 1 to 3 were gained. Spectroscopic analysis in addition to HRMS, FTIR, 1D and 2D NMR analysis were utilized to determine the chemical structure. After that, compounds 1 to 3 were tested against breast cancer, melanoma as well as normal kidney cells (MCF-7, B16-F10, and CV-1, respectively). The resulted cytotoxicity test revealed that compound 1 had the best cytotoxicity against all cells compared with the other isolated compounds. This result suggests that the pentacyclic triterpenoid core in compound 1 increases cytotoxicity compared with a tetracyclic skeleton
Pengembangan Alat Portabel Pengukur Kadar Air dan Suhu Biji Kopi Berbasis ESP32 dengan Sensor Kapasitif dan Penyimpanan Data Real-Time
Full text linkThe primary quality indicator of coffee beans is determined by their moisture content. This study aims to develop a portable prototype device for measuring both the moisture content and temperature of coffee beans, utilizing an ESP32 microcontroller integrated with a Capacitive Soil Moisture Sensor v1.0 and an SHT21 sensor. The device is designed to provide accurate and efficient measurements, with results displayed in real time on an OLED screen. In addition, the system stores measurement data on an SD card for further analysis. Experimental testing was conducted five times for each sample, comparing the results of the prototype with reference instruments, namely the YL-69 sensor for moisture measurement and a digital thermometer for temperature measurement. The results demonstrated that the device achieved a high level of accuracy, with an average relative error of 1.05% for moisture content and 0.91% for temperature. Furthermore, the prototype was proven to be portable and energy-efficient, consuming 7.7 Wh over 1.1 hours of operation, as evaluated through battery-based performance testing until full discharge. With its integrated data storage and real-time monitoring capabilities, this device provides a practical solution for coffee farmers and processors in maintaining and ensuring the quality of coffee beans.Indikator utama kualitas pada biji kopi dipengaruhi oleh tingkat kadar air pada biji kopi. Penelitian ini bertujuan untuk mengembangkan prototype alat pengukur kadar air dan suhu biji kopi portable berbasis ESP32 yang dilengkapi dengan sensor kapasitif v1.0 (Capacitive Soil Moisture v1.0) dan sensor SHT21. Alat ini dirancang untuk memberikan pengukuran yang akurat dan efisien, dengan hasil yang ditampilkan secara real-time pada layar OLED. Selain itu, alat ini juga menyimpan data pengukuran ke dalam kartu SD untuk keperluan analisis lebih lanjut. Pengujian dilakukan sebanyak 5 kali setiap sampel dengan membandingkan hasil pengukuran alat yang dibuat dengan alat pembanding, yaitu sensor YL-69 untuk kadar air dan termometer digital untuk suhu. Hasil pengujian menunjukkan bahwa alat ini memiliki tingkat akurasi tinggi dengan kesalahan relatif rata-rata sebesar 1,05% untuk kadar air dan 0,91% untuk suhu. Alat ini juga terbukti portabel dan hemat daya dengan hasil konsumsi energi sebesar 7,7 Wh selama 1,1 jam pengoperasian melalui tahap evaluasi yang mencakup pengoperasian alat menggunakan baterai dalam kondisi terisi penuh, diukur berdasarkan durasi penggunaan perangkat hingga daya baterai habis sepenuhnya. Dengan fitur penyimpanan data dan pemantauan real-time, alat ini dapat menjadi solusi bagi petani dan pengolah kopi dalam menjaga kualitas biji kopi
The Perkembangan Visualisasi Ilustrasi Cerita Pendek Majalah Bobo Tahun 1975-1985: Perkembangan Visualisasi Ilustrasi Cerita Pendek Majalah Bobo Tahun 1975-1985
No full textBobo Magazine is one of the popular children's readings that remains popular to this day. Bobo Magazine was first published in 1973 during the New Order era. From 1975 to 1985, book publishing in Indonesia experienced rapid growth due to national development, and during that time, there were advancements in the visualization of illustrations in Bobo Magazine's short stories.This study aims to determine the factors that contribute to the development of illustration visualization in Bobo Magazine. The data used consists of documentation of Bobo Magazine's short story illustrations from 1975 to 1985. The obtained data was then observed and reviewed through literature studies to identify the factors that caused the advancement of illustrations during that period, including both social factors and technological advancements that contributed to the progress of illustration in IndonesiaMajalah Bobo merupakan salah satu bacaan anak yang populer hingga saat ini. Majalah Bobo diterbitkan pada tahun 1973 di masa Orde Baru. Selama tahun 1975-1985, penerbitan buku di Indonesia berkembang pesat karena pembangunan nasional, selama masa itu terdapat perkembangan visualisasi ilustrasi cerita pendek Majalah Bobo.Penelitian ini bertujuan untuk mengetahui faktor-faktor penyebab perkembangan visualisasi ilustrasi Majalah Bobo. Data yang digunakan adalah dokumentasi ilustrasi cerita pendek Majalah Bobo dari tahun 1975-1985, data yang diperoleh kemudian diobservasi dan dilakukan studi pustaka untuk mengetahui faktor penyebab perkembangan ilustrasi di masa itu, baik faktor sosial maupun kemajuan teknologi yang mendorong kemajuan ilutrasi di Indonesia
Multimodal Discourse Analysis of Studio Ghibli Movie Posters: (Study of Studio Ghibli Movie Posters 1984-2023)
Full text linkGhibli Studio's animated film posters are visually beautiful, with a unique, alluring art style that reflects the story's essence. The images of the posters are eye-catching and portray nuances and emotions that have become very iconic in the world of animation. This research method used Fairclough's critical discourse analysis model and Kress and van Leeuwen's visual grammar in the context of visual semiotics to find the meaning behind the posters of Studio Ghibli animated films. The research method used was multimodal discourse analysis combined with a descriptive qualitative approach and quantitative narratives. The purpose of this study was to identify the use of a specific visual language in Studio Ghibli film posters, employing the visual grammar framework of three metafunctions in semiotics as an explorative tool to find out how these elements can strengthen visual messages and themes within the multimodal discourse analysis framework. The contribution of this research is the examination of the visual and textual aspects of film poster media to increase public awareness of the importance of discourse analysis in interdisciplinary science, namely the combination of visual communication design and systemic functional linguistics (SFL).Analisis multimodal wacana kritis yang merupakan gabungan dari analisis multimodal dan analisis wacana kritis merupakan kajian yang mampu membongkar makna di balik objek penelitian multimodal. Metode dalam penelitian ini model analisis wacana kritis Fairclough, dan visual grammar Kress dan van Leeuwen dalam konteks analisis semiotik visual, yang di gunakan sebagai “pisau bedah” dalam mencari makna dibalik poster-poster film animasi yang diproduksi oleh Studio Ghibli. Dengan menggunakan metode deskriptif kualitatif, yang dinarasikan secara kuantitatif. Multimodal adalah salah satu konsep yang di tawarkan dalam kerangka kerja Kress dan van Leeuwen dan konsep tersebut akan berbentuk analisis wacana multimodal. Kontribusi penelitian ini adalah bagaimana mengkaji aspek visual dan tekstual dalam media poster film untuk meningkatkan kesadaran masyarakat akan pentingnya discourse analisis untuk menambah ilmu pengetahuan lintas disiplin yaitu kombinasi desain komunikasi visual dan Linguistik fungsional sistemik (SFL). Tujuan penelitian ini adalah mengidentifikasi penggunaan bahasa visual khusus dalam poster, Framework visual grammar tiga metafungsi dalam semiotika, dan visual grammar yang sebagai alat eksplorasi. Tujuannya adalah untuk mengeksplorasi bagaimana elemen-elemen ini digunakan untuk memperkuat pesan visual dan tema dalam kerangka analisis wacana multimodal
Optimasi Parameter Pencetakan dan Evaluasi Sifat Mekanis Filamen Poliuretan Termoplastik dalam Pencetakan 3D
Full text linkTermoplastik poliuretan (TPU) merupakan salah satu jenis polimer termoplastik yang saat ini sangat menarik perhatian pengguna mesin pencetakan 3D. Filamen TPU memiliki sifat elastis, kekuatan tarik dan ketahanan terhadap benturan yang baik sehingga sangat potensial untuk digunakan dalam proses pembuatan produk pada berbagai aplikasi. Walaupun demikian, dikarenakan sifat elastisnya, proses pencetakan TPU dinilai cukup sulit sehingga perlu dilakukan kajian untuk mengidentifikasi kecepatan cetak, kecepatan retraksi, temperatur cetak, dan jarak retraksi optimum untuk mencetak filamen TPU. Dalam penelitian ini, dilakukan kajian terkait penentuan parameter cetak optimum untuk mencetak filamen TPU. Parameter cetak optimum yang diperoleh kemudian digunakan untuk mencetak sampel pengujian tarik. Pengujian tarik pada sampel yang dihasilkan dilakukan dengan mengacu pada ASTM D 638-14. Berdasarkan hasil penelitian yang dilakukan, temperatur cetak, kecepatan cetak, jarak retraksi dan kecepatan retraksi optimum untuk mencetak filamen TPU adalah sebesar 230°C, 40 mm/s, 1 mm, dan 40 mm/s secara berturut-turut. Sampel yang dicetak dengan arah 0 memiliki kekuatan tarik yang lebih tinggi dibandingkan dengan spesimen yang dicetak dengan arah 90°
Karakterisasi Fisik dan Mekanik Papan Komposit Serat Kelapa dan Limbah Plastik Pet Mengacu pada Standar SNI 03-2105-2006
Full text linkThis study aims to determine the physical and mechanical properties of composite board (density, moisture content, thickness swelling, elastic modulus and fracture modulus) of coconut fiber and PET polyethylene etilen terephalate plastic waste by referring to the SNI 03-2105-2006 standard with four comparison of coconut fiber composition : PET plastic : 157 yukalac resin (0:0:100; 5:5:90; 10:10:80; and 20:20:60) %. This research was conducted by varying the composition of coconut fiber, PET plastic and 157 yukalac resin, then tested the physical properties and mechanical properties of the composite board, the test parameters were density, moisture content ranged from 1.1026 to 1.1419 gr/cm³, moisture content ranged from 0.7379 to 2.3597 %, thickness development ranged from 0.326 to 0.602 %, the modulus of elasticity ranged from 5,566.71 to 34,317.48 kgf/cm², and the fracture modulus ranged from 153.34 kgf/cm² to 447.02 kgf/cm². The conclusion from the results of the tests carried out is that the more coconut fiber and PET plastic are added, the better the physical and mechanical properties are, in general the resulting composite board meets SNI 03-2105-2006 standards except for density.Penelitian ini bertujuan untuk mengetahui sifat fisik dan mekanik papan komposit (massa jenis, kadar air, pengembangan ketebalan, modulus elastisitas, dan modulus patah) berbahan dasar sabut kelapa dan limbah plastik PET, berdasarkan standar SNI 03-2105-2006, dengan menggunakan empat variasi komposisi sabut kelapa, plastik PET, dan resin Yukalac 157 (0:0:100; 5:5:90; 10:10:80; dan 20:20:60). Penelitian ini dilakukan dengan memvariasikan komposisi sabut kelapa, plastik PET dan resin yukalac 157, kemudian dilakukan pengujian sifat fisis dan sifat mekanik papan komposit, parameter pengujiannya adalah densitas, kadar air berkisar antara 1,1026 – 1,1419 gr/cm³, kadar air konten berkisar antara 0,7379 hingga 2,3597 %, pengembangan ketebalan berkisar antara 0,326 hingga 0,602 %, modulus elastisitas berkisar antara 5.566,71 hingga 34.317,48 kgf/cm², dan modulus patah berkisar antara 153,34 kgf/cm² hingga 447,02 kgf/cm². Kesimpulan dari hasil pengujian yang dilakukan adalah semakin banyak penambahan sabut kelapa dan plastik PET maka sifat fisik dan mekaniknya semakin baik, secara umum papan komposit yang dihasilkan memenuhi standar SNI 03-2105-2006 kecuali kepadatan
Negotiating the Waves and Tides of Life: Challenges, Opportunities, and Coping of Skimboarders in Dahican, Mindanao, Philippines
Full text linkEmploying qualitative methods, particularly phenomenological research designs, this study explored the lived experiences and coping strategies of skimboarders in Dahican, Mindanao. Studies have shown varying effects of ecotourism on locals. In this study, the result shows the existence of affirmative and negative effects of tourism. Skimboarders faced physical struggles in learning the sport due to its technical difficulty, high temperatures, and exhaustion. On the emotional and psychological struggles, dealing with unforgiving tourist who treats them as mere commodities or human beings being paid to serve at their disposal. The wanton abuse of the environment, where tourists are inconsiderate of leaving trash anywhere along the coastlines. On the other hand, the result also showed an affirmative effect on skimboarders. Among these were livelihood chances. The tourism industry provides income for skimboarders through tutorials, and these fees are used for their daily expenses. Further, improved interpersonal relations also appeared. By dealing with tourists, skimboarders developed their skills in customer relations. Lastly, they improved their advocacy for the environment through marine life protection. Coastal clean-ups and the development of turtle hatcheries increase their love for the environment, especially the sea. The result of this study greatly contributes to the growing knowledge and literature on the lives of skimboarders by understanding their opportunities and challenges.
An Investigation on the Crisis Management Practices of Boutique Hotels and Villas in Sri Lanka: Lessons from the COVID-19 Era
Full text linkThis study investigates the key crisis experiences and coping management strategies adopted by boutique hotels and villas in Sri Lanka with specific reference to the coronavirus (COVID-19) pandemic and the subsequent economic downturn era in Sri Lanka. A qualitative research method was adopted in conducting the study. Data was gathered using eight semi-structured interviews targeting general managers of registered boutique hotels and villas in Sri Lanka, selected through the snowball sampling technique. The thematic analysis was conducted to extract the main ideas from the transcripts. The study's results revealed infrastructural discrepancies, strategy risk, and distorted supply chains as three key crisis experiences encountered by boutique hoteliers in Sri Lanka during the period under study. Three key coping strategies were discovered as those predominantly used by boutique hoteliers during the crises, stressing the importance of product diversification, marketing efforts, and revamping supply chains. This study urges hoteliers to enhance crisis resilience through strategic adjustments, including restructuring supply chains via local partnerships for authenticity and cost benefits. It also raises caution to governments, emphasizes proactive planning for national resilience, especially in infrastructure, and advocates for active government involvement/participation in the tourism sector
Wawasan Berbasis Gender terhadap Niat Berkelanjutan dalam Penggunaan Aplikasi Kesehatan Seluler di Indonesia: Studi Pascapandemi tentang Persepsi Ancaman Penyakit dan Efikasi Diri
Full text linkThe sustained use of mobile health applications (mHealth) in the post-pandemic era is increasingly relevant due to ongoing health concerns and perceived disease threats (PDT). This study addresses significant gaps in understanding how self-efficacy and gender differences influence continuance intention (CI) to use mHealth applications. Guided by the Protection Motivation Theory (PMT), the research examines therelationships between PDT, self-efficacy, and CI, with gender as a moderating variable. Data from 415 mHealth users in Indonesia were analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM). The findings reveal that PDT significantly influences CI, while self-efficacy directly enhances CI. Gender moderates the PDT-CI relationship, with female users showing a stronger connection. However, self-efficacydoes not mediate the PDT-CI relationship. The study highlights practical implications for mHealth developers, including the need for user-friendly and gender-sensitive designs to enhance self-efficacy and engagement. Limitations include the cross-sectional design and focus on Indonesian users, suggesting future research should adopt longitudinal approaches and explore diverse demographic and cultural contexts. The findings extend PMT's theoretical application and provide actionable insights for improving mHealth application adoption and retention in diverse populations.Penggunaan aplikasi kesehatan seluler (mHealth) yang berkelanjutan di era pascapandemi semakin relevan karena adanya kekhawatiran kesehatan yang terus berlangsung dan persepsi ancaman penyakit (perceived disease threats/PDT). Penelitian ini mengisi kesenjangan dalam pemahaman tentang bagaimana self-efficacy dan perbedaan gender memengaruhi continuance intention (CI) untuk menggunakan aplikasi mHealth. Dengan menggunakan protection motivation theory (PMT) sebagai dasar teoritis dikaji hubungan antara PDT, self-efficacy, dan CI, dengan gender sebagai variabel moderasi. Data dari 415 pengguna mHealth di Indonesia dianalisis menggunakan metode partial least squares structural equation modeling (PLS-SEM). Hasil penelitian menunjukkan PDT berpengaruh signifikan terhadap CI, sementara self-efficacy secara langsung meningkatkan CI. Selain itu, gender memoderasi hubungan antara PDT dan CI, pengguna perempuan menunjukkan hubungan yang lebih kuat. Namun, self-efficacy tidak memediasi hubungan antara PDT dan CI. Implikasi praktis penelitian ini adalah pentingnya pengembangan aplikasi mHealth yang ramah pengguna, sensitif gender, dan mampu meningkatkan self-efficacy untuk meningkatkan keterlibatan pengguna. Batasan penelitian mencakup desain cross-sectional dan fokus geografis di Indonesia, sehingga penelitian di masa depan disarankan menggunakan desain longitudinal dan mengeksplorasi konteks demografis serta budaya yang lebih beragam. Temuan ini memperluas aplikasi teoritis PMT dan memberikan wawasan praktis untuk meningkatkan adopsi serta retensi aplikasi mHealth
Mosaik Peradaban: Interaksi Manusia dan Kebudayaan
Full text linkThe author in this book emphasizes that culture is an entity that continues to develop, starting from simple forms to reaching higher complexity. This development not only functions as a means of adaptation, but also as a way for humans to find solutions to the various challenges they face. More than that, culture is a reflection of the human way of life which is based on a system and symbols of values, which ultimately places humans in a transcendent reality