Langkawi's Ecological and Economic Renaissance: A Study of Blue and Green Opportunities

This article delves into the potential of the blue and green sectors situated in Langkawi Island, Malaysia. With its abundant marine and terrestrial resources, the island needs to strike a balance between its economic growth and environmental preservation imperatives. By leveraging the potential of green and blue sectors such as tourism, fisheries, renewable energy, agriculture, and forestry, Langkawi Island can serve as a model for responsible development, all while preserving its innate natural beauty and biodiversity. A survey was conducted involving 104 local respondents at various attraction points across Langkawi Island to assess the progress of these sectors. Overall, the respondents were predominantly in agreement regarding the impacts of development stemming from both the blue and green economies, coupled with the positive spill-over effects witnessed on the island. The descriptive findings indicate that the potential for growth within these blue and green economies is promising, buoyed by anticipation from both governmental and private sectors. As such, it becomes imperative for policymakers to formulate a comprehensive development plan that can adequately bolster the expansion of these sectors. This preparation will be crucial in ensuring the sustainable growth of Langkawi Island's blue and green economies, ultimately fostering a harmonious coexistence between economic progress and environmental conservation.Artikel ini mengulas potensi sektor biru dan hijau yang berlokasi di Pulau Langkawi, Malaysia. Dengan sumber daya laut dan darat yang melimpah, pulau ini perlu menemukan keseimbangan antara pertumbuhan ekonomi dan keharusan pelestarian lingkungan. Dengan memanfaatkan potensi sektor hijau dan biru seperti pariwisata, perikanan, energi terbarukan, pertanian, dan kehutanan, Pulau Langkawi dapat menjadi contoh pengembangan yang bertanggung jawab, sekaligus menjaga keindahan alam dan keanekaragaman hayatinya yang asli. Untuk menilai perkembangan sektor-sektor ini, dilakukan survei yang melibatkan 104 responden lokal di berbagai titik atraksi di Pulau Langkawi. Secara keseluruhan, responden sebagian besar sepakat mengenai dampak pembangunan yang berasal dari kedua sektor ekonomi biru dan hijau, serta efek positif yang terlihat di pulau ini. Temuan deskriptif menunjukkan bahwa potensi pertumbuhan dalam sektor ekonomi biru dan hijau ini sangat menjanjikan, didukung oleh antisipasi dari sektor pemerintah dan swasta. Oleh karena itu, menjadi sangat penting bagi pembuat kebijakan untuk merumuskan rencana pembangunan yang komprehensif yang dapat memadai memperkuat perluasan sektor-sektor ini. Persiapan ini akan menjadi kunci untuk memastikan pertumbuhan berkelanjutan dari ekonomi biru dan hijau Pulau Langkawi, akhirnya mendorong keberadaan harmonis antara kemajuan ekonomi dan pelestarian lingkungan

On Data Driven SIRD Model of Delta and Omicron Variants of COVID-19

The compartmental model stands as a cornerstone in quantitatively describing the transmission dynamics of diseases. Through a series of assumptions, this model can be formulated and subsequently validated against real-world conditions. Leveraging the abundance of COVID-19 data presently available, this study endeavors to reverse engineer the model construction process. Specifically, we analyse the compartmental model governing two notable variants of COVID-19: Delta and Omicron, utilizing empirical data. Employing the SINDy method, we extract parameters that define the model by effectively fitting the available data. To ensure robustness, the obtained model undergoes validation via comparison with real-world data through numerical integration. Additionally, we conduct fine-tuning in regularization techniques and input features to refine model selection. The constructed model then undergoes thorough analysis to gain qualitative insights and interpretations regarding the transmission dynamics of COVID-19

Simulation of Ultra-Short Laser Pulses Propagation and Ionization in Dual-Gas-Cells to Enhance the Quasi-Phase Matching of Harmonics Generation in Plasmas

A numerical model was designed and implemented to investigate the influence of plasma defocusing on laser characteristics. The effects of plasma defocusing were investigated by studying beam divergence, intensity reduction, and blue shifting. The diffusion of the ultra-intense laser beam in gas cells was within a Rayleigh range. Moreover, using dual-gas-cells, the impact of quasi-phase matching (QPM) on the creation of harmonic pulses in argon and hydrogen plasmas was studied. The alternating structure of argon and hydrogen gas cells showed a perfect build-up of the generated ultra-short harmonics pulses. The impact of electron density on laser diffusion and the creation of harmonic pulses were also investigated in this work. In the simulation, argon plasma with different plasma densities was used in an alternating structure to create dual-gas-cells and quasi-phase-matching. Noticeable conversion of the fundamental laser pulses to harmonics pulses was accomplished in the model by using the QPM concept

Particle Size Optimization of Melinjo (Gnetum gnemon L.) Seed Hardshell: A Potential Antioxidant Alternative

Natural ingredients can have extraordinary potential as alternative medicines due to their accessibility and cost-effectiveness. Application of these ingredients should consider solubility and permeability, which determine the success of pharmaceutical characteristics formulation and biological activity indication. In this context, physical manipulation, specifically particle size reduction, is an effective strategy to address these issues. Previous research has explored active compounds in the stilbenoid group, found in the outer skin, hard shell, and endosperm of melinjo (Gnetum gnemon L.) seeds, functioning as antioxidant. Based on the potential as antioxidant, stilbenoid compounds, including resveratrol, contained in melinjo seed hardshell have shown significant pharmacological effects. Therefore, this research aimed to investigate the potential of melinjo seed hardshell extract as a natural antioxidant alternative by modifying the particle size through a grinding process to obtain nanoparticles. The analysis was carried out using ball milling to enhance the solubility of melinjo seed hardshell extract by increasing the saturated solubility and surface area of the particles. The results showed that the total phenol content and the antioxidant power increased significantly (p < 0.05) after ball milling. Melinjo seed hardshell nanoextract is reported herein as a promising source of natural antioxidant from local Indonesian plants

Commuting Behaviors of People with Disabilities and the Implications for Transport Planning and Policy: A Preliminary Study

This research aimed to obtain an initial understanding of the commuting behaviors of people with disabilities, which has not been widely discussed in the transportation planning literature in Indonesia. Facets studied included frequency of weekly commuting; trip duration to the workplace; trip chaining behavior; usage of public transportation; and utilization of private vehicles. Commuting trips were limited to the home-work-home context, and the research was conducted on adult disabled commuters (aged 17 to 60) in the Jakarta Metropolitan Area (Jabodetabek). A total of 51 commuters with motor and sensory (visual and auditory) disabilities participated in the survey. The results indicate that people with disabilities tend to spend more hours commuting; use public transportation, with the TransJakarta Bus Rapid Transit and paratransit in the form of online motorcycle taxis as the primary modes of transport; and engage in pre-planned trip chaining activities, primarily for visiting family, friends, and clients as well as doing grocery shopping and getting medical treatment. The research findings can serve as valuable resources for developing inclusive transportation policies and planning, such as improving and enhancing access to public transportation for people with disabilities, supporting inclusive training policy in the public transportation field, implementing TOD strategies, and advancing transportation technology to enhance convenience for people with disabilities

Exploring Public Sentiments Using Big Data on Superhub Spatial Development of Nusantara, the New Capital City of Indonesia

Superhub development is crucial for enhancing the economic prowess and sustainability of a region, focusing on bolstering its global competitiveness and amplifying its impact on national and regional growth. In the case of Nusantara, Indonesia’s new capital city, understanding public sentiment towards its development plan is essential. This study employed sentiment analysis, combining a comprehensive dataset of 433,637 tweets from 2020 with public documents and machine-learning tools to accurately gauge public opinion. Six key components of regional development emerged from the analysis, reflecting public discourse on IKN’s planning and execution. Geographically, sentiment across the 33 provinces was evenly distributed, with 63% positive, 24% negative, and 13% neutral sentiments observed in the tweets. However, sentiment fluctuated throughout the year, with a surge in negative sentiment early in 2020 due to concerns over financing risks and economic challenges. Nonetheless, negativity waned as the year progressed, with positive tweets steadily increasing from April to December. These findings offer valuable insights for guiding the development of Nusantara, aiding policymakers in addressing public concerns, and ensuring a more informed and inclusive approach. Such sentiment analysis proves instrumental in shaping the strategic trajectory of the new capital city, fostering sustainable growth and public support

Evaluasi Spasial Estimasi Curah Hujan pada Radar Cuaca Menggunakan Metode Z-R Marshall-Palmer di Wilayah Jawa Barat

Rainfall is one of the weather parameters that affect various sectors. High rainfall intensity can trigger hydrometeorological disasters, so rainfall observation data is vital to monitor rainfall conditions in an area. An automatic rain gauge is an instrument that measures rainfall at an observation point, but the instrument has reasonably low coverage and has yet to reach the entire region. Weather radar is a remote sensing instrument capable of spatially estimating rainfall. Weather radar data can be used to estimate rainfall using the Marshall-Palmer Z-R method. The application of the method can be an alternative for areas that do not have rainfall observation equipment. However, the estimation needs to be evaluated to improve the accuracy of the estimation value. Based on the evaluation, the highest coefficient of determination was 0.92, and the lowest was 0.67. The lowest RMSE value was 2.40, the highest was 6.76, the highest ME value was 16.59, and the lowest was 5.93; the highest bias was 12.90, and the lowest was 5.30. The study results show that the weather radar can operate according to the specifications of the maximum observation distance of up to 220 KM, but the farther the observation distance to a point, the higher the performance of rainfall estimation accuracy.Curah hujan merupakan salah satu parameter cuaca yang berpengaruh terhadap berbagai sektor. Intensitas curah hujan tinggi dapat memicu terjadinya bencana hidrometeorologi sehingga data pengamatan curah hujan sangat penting untuk memantau kondisi curah hujan di suatu wilayah. Peralatan curah hujan otomatis merupakan instrumen mengukur curah hujan di suatu titik pengamatan, namun peralatan tersebut memiliki cakupan yang cukup rendah dan belum menjangkau seluruh wilayah. Radar cuaca merupakan salah satu instrumen penginderaan jauh yang mampu mengestimasi curah hujan secara spasial. Output data pengamatan radar cuaca dapat dijadikan estimasi curah hujan menggunakan metode pendekatan Z-R Marshall-Palmer. Penerapan metode tersebut dapat menjadi alternatif untuk wilayah yang belum memiliki peralatan pengamatan curah hujan. Namun, estimasi tersebut perlu dievaluasi sehingga dapat meningkatkan perfoma akurasi nilai estimasi tersebut. Berdasarkan evaluasi yang telah dilakukan, koefisien determinan tertinggi sebesar 0,92 dan terendah sebesar 0,67. Nilai RMSE terendah sebesar 2.40 dan tertinggi sebesar 6.76, nilai ME tertinggi sebesar 16.59 dan terendah 5.93, bias tertinggi sebesar 12,90 dan terendah 5.30. Hasil studi menunjukkan radar cuaca dapat beroperasi sesuai spesifikasi jarak maksimal pengamatan hingga 220 KM, namun semakin jauh jarak pengamatan terhadap suatu titik, mempengaruhi performa akurasi estimasi curah hujan

Sistem Arsitektur Manajemen Bangunan untuk Memaksimalkan Swakonsumsi pada Bangunan Universitas: Studi Kasus

Due to its intermittent nature, significant adoption of solar PV into the grid can decrease grid reliability. One solution to increase it is to increase PV self-consumption with two methods: adding Energy Storage System (ESS) and conducting Demand Side Management (DSM). University building has a distinct characteristic in its complex dynamics. Therefore, there is a lack of research to control both methods of increasing self-consumption. This paper aimed to do an integrated literature review on increasing self-consumption and then propose a system architecture recommendation for university building management based on the review. The Smart Grid Architectural Model (SGAM) evaluated the case study object. The result showed that a data-driven controller has been chosen as the most suitable controller for the university building management system. The data needed to build a data-driven controller could be obtained through readily available sensors in the case study object, making it feasible for implementation.Dikarenakan sifatnya yang intermitten, adopsi energi dari PV surya ke dalam jaringan dapat mengurangi keandalan jaringan. Salah satu solusi untuk meningkatkannya adalah dengan meningkatkan swakonsumsi PV dengan dua metode: menambahkan Sistem Penyimpanan Energi (SPBE) dan melakukan manajemen sisi permintaan. Gedung universitas memiliki karakteristik yang berbeda dalam dinamika kompleksnya. Kurangnya penelitian untuk mengendalikan kedua metode ini di gedung-gedung universitas disebabkan oleh karakteristik ini. Makalah ini bertujuan untuk melakukan tinjauan literatur terintegrasi tentang upaya meningkatkan konsumsi sendiri kemudian mengusulkan rekomendasi arsitektur sistem untuk manajemen gedung universitas berdasarkan tinjauan tersebut. Kami kemudian mengevaluasi objek studi kasus menggunakan Smart Grid Architecture Model (SGAM). Hasilnya menunjukkan bahwa pengendali berbasis data telah dipilih sebagai pengendali yang paling cocok untuk sistem manajemen gedung universitas

Analisis Perancangan Dinding Penahan Tanah Untuk Seawater Intake Pembangkit Listrik Tenaga Uap

Abstract The handling of retaining walls in the PLTU seawater intake project is a crucial part in maintaining the stability of buildings below ground level. The retaining wall construction is selected based on the depth of excavation, soil type, the height of the Groundwater Table (GWT), and the load being retained. The lateral force calculation method uses Rankine and Coulomb theories with specified soil parameters. The case study was conducted at the seawater intake area of Java 9 & 10 Suralaya PLTU in Suralaya, Cilegon, Banten. The design process involved soil data interpretation, site class determination, and stability analysis using MIDAS GTS NX software. The retaining wall design is divided into two parts, using diaphragm walls and secant piles. The use of lateral reinforcement in the form of soil anchors is adjusted to the provisions of SNI 8460-2017. The design results show that the wall and anchor configurations meet the design criteria, with appropriate values of safety numbers and lateral deflections. However, the selection of Mohr-Coulomb soil model and pseudostatic earthquake analysis produced more conservative results. In conclusion, the retaining wall design proved to be effective in handling the lateral soil loads and pressures in the seawater intake PLTU project.Abstrak Penanganan dinding penahan tanah pada proyek seawater intake PLTU merupakan bagian krusial dalam menjaga kestabilan bangunan di bawah permukaan tanah. Konstruksi dinding penahan tanah dipilih berdasarkan kedalaman galian, jenis tanah, ketinggian Muka Air Tanah (MAT), dan beban yang ditahan. Metode perhitungan gaya lateral menggunakan teori Rankine dan Coulomb dengan parameter-parameter tanah yang ditentukan. Studi kasus dilakukan pada area seawater intake PLTU Jawa 9 & 10 Suralaya di Suralaya, Cilegon, Banten. Proses perancangan melibatkan interpretasi data tanah, penentuan kelas situs, dan analisis stabilitas menggunakan perangkat lunak MIDAS GTS NX. Desain dinding penahan tanah dibagi menjadi dua bagian, dengan menggunakan dinding diafragma dan secant pile. Penggunaan perkuatan lateral berupa angkur tanah disesuaikan dengan ketentuan SNI 8460-2017. Hasil perancangan menunjukkan konfigurasi dinding dan angkur yang memenuhi kriteria desain, dengan nilai angka keamanan dan defleksi lateral yang sesuai. Meskipun demikian, pemilihan model tanah Mohr-Coulomb dan analisis gempa pseudostatik menghasilkan hasil yang lebih konservatif. Kesimpulannya, desain dinding penahan tanah terbukti efektif dalam menangani beban dan tekanan lateral tanah pada proyek seawater intake PLTU

Performance of Interconnected Hybrid ZigBee-Optic for Extended Wireless Sensor Networks

Wireless sensor networks (WSNs) are widely used to monitor remote areas far away from the monitoring center. For large-scale or high-capacity WSNs, when they contain many sensor nodes, a transmission system with low latency and large bandwidth is required. In order to extend the network range, the use of optical communication is one of the alternatives to provide more capacity and a longer range. This study discusses the performance of a range-extended WSN utilizing a hybrid of ZigBee and optic transmission. The performance of the proposed method was evaluated by analyzing the throughput, delay per meter, package loss, and error, which were then compared to a ZigBee-Wifi based system. The experimental results showed that the throughput of the hybrid ZigBee-Fiber Optic (ZigBee FO) system was about 12% greater than that of the ZigBee-Wifi system, and it transmitted the sensor data with a significantly lower delay, reduced by 83%, compared to the ZigBee-Wifi. The package loss and error of ZigBee-FO was 35.7% lower than that of ZigBee-Wifi. Based on these results, the ZigBee-FO WSN has the advantage of significantly improving network performance by reducing the transmission delay, therefore it is beneficial in extending the WSN range