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Studi Komparasi Standar Desain Pembebanan Angin Untuk Bangunan Tinggi
Full text linkAbstrak
Indonesia dan beberapa negara tetangganya mengadopsi standar pembebanan angin internasional seperti ASCE, Eurocode, AIJ, AS/NZS, dan NBCC, yang dikembangkan pada kondisi geografis yang berbeda dibandingkan dengan daerah Asia Tenggara, sehingga diperlukan studi komparasi untuk mengetahui perbedaan fundamental dalam pembebanan angin dan hasil respons struktur yang didapatkan dari masing-masing standar pembebanan dengan kondisi angin di Indonesia. Hasil studi komparasi menunjukkan bahwa secara garis besar, masing-masing standar pembebanan menggunakan pendekatan yang sama dalam menentukan beban angin. Perbedaan utama terdapat pada periode ulang kecepatan angin yang digunakan dan nilai averaging time yang digunakan untuk menghitung faktor hembusan. Kemudian, terdapat juga perbedaan pada faktor-faktor lingkungan yang diperhitungkan untuk mendapatkan tekanan velositas, penggunaan persamaan dan nilai gust effect factor serta koefisien tekanan, dan perhitungan beban angin di masing-masing arah pada tiap standar. Studi komparasi ini juga menunjukkan bahwa untuk sebuah kasus struktur tinjauan berupa bangunan super tinggi yang berlokasi di Jakarta, standar pembebanan ASCE memberikan beban angin dan respons struktur terbesar.
Kata-kata Kunci: Beban angin, komparasi pembebanan angin, respons struktur, standar pembebanan angin, struktur super tinggi
Abstract
Indonesia and its neighboring countries adopt international wind loading standards, such as ASCE, Eurocode, AIJ, AS/NZS and NBCC, which are developed in different geographical conditions compared to South-East Asia region. Thus, a comparative study is needed to see the fundamental differences in wind loading and structure response obtained from each loading standards with Indonesia’s wind condition. Comparative study shows that in general, each loading standards use the same approach in calculating wind load. The main differences of each loading standards come from the return period of the wind speed used in calculating wind load and averaging time used in calculating gust factor. Each standard also has differences in the factors used to calculate velocity pressure, the expression and method of gust effect factor and pressure coefficient, and methods for calculating all three directions of wind load in each standard. This study also shows that for the observed structure located in Jakarta used in this study, ASCE standard gives the highest value of design wind load and structure response.
Keywords: Wind load, wind loading comparison, structural response, wind loading standards, supertall structureAbstrak
Indonesia dan beberapa negara tetangganya mengadopsi standar pembebanan angin internasional seperti ASCE, Eurocode, AIJ, AS/NZS, dan NBCC, yang dikembangkan pada kondisi geografis yang berbeda dibandingkan dengan daerah Asia Tenggara, sehingga diperlukan studi komparasi untuk mengetahui perbedaan fundamental dalam pembebanan angin dan hasil respons struktur yang didapatkan dari masing-masing standar pembebanan dengan kondisi angin di Indonesia. Hasil studi komparasi menunjukkan bahwa secara garis besar, masing-masing standar pembebanan menggunakan pendekatan yang sama dalam menentukan beban angin. Perbedaan utama terdapat pada periode ulang kecepatan angin yang digunakan dan nilai averaging time yang digunakan untuk menghitung faktor hembusan. Kemudian, terdapat juga perbedaan pada faktor-faktor lingkungan yang diperhitungkan untuk mendapatkan tekanan velositas, penggunaan persamaan dan nilai gust effect factor serta koefisien tekanan, dan perhitungan beban angin di masing-masing arah pada tiap standar. Studi komparasi ini juga menunjukkan bahwa untuk sebuah kasus struktur tinjauan berupa bangunan super tinggi yang berlokasi di Jakarta, standar pembebanan ASCE memberikan beban angin dan respons struktur terbesar.
Kata-kata Kunci: Beban angin, komparasi pembebanan angin, respons struktur, standar pembebanan angin, struktur super tinggi
Abstract
Indonesia and its neighboring countries adopt international wind loading standards, such as ASCE, Eurocode, AIJ, AS/NZS and NBCC, which are developed in different geographical conditions compared to South-East Asia region. Thus, a comparative study is needed to see the fundamental differences in wind loading and structure response obtained from each loading standards with Indonesia’s wind condition. Comparative study shows that in general, each loading standards use the same approach in calculating wind load. The main differences of each loading standards come from the return period of the wind speed used in calculating wind load and averaging time used in calculating gust factor. Each standard also has differences in the factors used to calculate velocity pressure, the expression and method of gust effect factor and pressure coefficient, and methods for calculating all three directions of wind load in each standard. This study also shows that for the observed structure located in Jakarta used in this study, ASCE standard gives the highest value of design wind load and structure response.
Keywords: Wind load, wind loading comparison, structural response, wind loading standards, supertall structur
Penentuan Kadar Selenium dalam Suplemen Kesehatan dengan Metode Spektrofotometri Menggunakan Reagen Kolorimetri 2,3-Diaminonaftalena
Full text linkHealth supplements containing selenium are now increasingly used by public . However, so far, a simple analytical method for determining selenium in health supplements are still rare. The latest method for determining selenium is based on Inductively Coupled Plasma (ICP) spectrometry. The cost of this method is very expensive. This study aims to apply and validate the UV-Vis Spectrophotometry method for determining selenium in health supplements using 2,3 Diaminonaphthalene as reagent. The study began by testing the specificity of reaction between Selenium with the reagent, that it is showed in specific spectrum with maximum absorbance wavelength at 483 nm. The linearity test using calibration curve, the results obtained were a linear regression equation y = 0.0126x + 0.0736 with the value of r2 = 0.9974 and Vx0 = 0.01%. Limit of detection = 0.00917 mg/mL and limit of quantitation = 0.02777 mg/mL. The accuracy of this method expressed as an average of % Recovery was 97.84% and the precision expressed as % RSD was 0.02%. The final step of this study was the determination of selenium in supplement samples using the standard addition method. The average results obtained based on the determination of selenium levels in supplements were 58.82% (sample A); 111.17% (sample B); and 98.08% (sample C) calculated against the selenium levels listed on the label of each sample, namely 25, 30, and 50 mg Se, with the requirement being in the range of 90 - 110% of the levels listed on the label. Thus, only sample C meets the requirements.Suplemen kesehatan yang mengandung selenium sekarang makin banyak diminati oleh masyarakat. Namun, sampai saat ini metode analisis yang sederhana untuk menentukan kadar selenium dalam suplemen kesehatan masih langka. Metode mutakhir penetapan selenium dalam sediaan adalah berbasis Inductively Coupled Plasma (ICP) yang membutuhkan biaya yang sangat mahal. Penelitian ini bertujuan untuk menerapkan dan memvalidasi metode Spektrofotometri UV-Vis untuk penentuan kadar selenium dalam suplemen kesehatan menggunakan pereaksi 2,3 Diaminonaftalen sebagai pereaksi pembentuk warna. Penelitian diawali dengan melakukan validasi metode analisis, di mana hasil uji spesifisitas reaksi antara selenium dengan peraksi 2,3 diaminonaftalen menunjukkan pola spektrum yang khas dengan panjang gelombang serapan maksimum pada 483 nm. Uji linearitas yang diperoleh berupa persamaan regresi linear y = 0,0126x + 0,0736 dengan nilai r2 = 0,9974 dan nilai Vxo = 0,01%. Batas deteksi = 0,00917 mg/mL dan Batas kuantitasi = 0,02777 mg/mL. Akurasi metode yang dinyatakan sebagai rata – rata % Rekoveri = 97,84% dan presisi metode yang dinyatakan sebagai %RSD = 0,02%. Langkah terakhir dalam penelitian ini adalah penetapan kadar selenium dalam sampel suplemen dari pasaran menggunakan metode standar adisi. Hasil rata-rata yang diperoleh berdasarkan penentuan kadar selenium dalam suplemen adalah 58,82% (sampel A); 111,17% (sampel B); dan 98,08% (sampel C) dihitung terhadap kadar selenium yang tercantum pada label setiap sampel yaitu 25, 30, dan 50 mg Se, dengan persyaratan berada pada rentang 90 - 110% dari kadar yang tertera pada label. Sehingga, hanya sampel C memenuhi persyaratan
UJI VALIDITAS DAN RELIABILITAS KUESIONER PDQ39 VERSI BAHASA INDONESIA PADA PASIEN PARKINSON
Full text linkThe PDQ-39 questionnaire is a disease-specific instrument used to measure the health-related quality of life (HRQoL) in Parkinson's disease patients. HRQoL assessment is one of key parameter for evaluating patient outcomes after receiving pharmacological and non-pharmacological treatments. The PDQ-39 questionnaire has been widely used in various countries, including Indonesia. However, no studies about validating and assessing the reliability of the Indonesian version of the PDQ-39 questionnaire have been published. This study aims to evaluate the validity and reliability of the Indonesian version of the PDQ-39 questionnaire. A cross-sectional study was conducted using a consecutive sampling technique. The study began with a language adaptation process. Questionnaire validity was assessed using Pearson’s Product-Moment correlation, while reliability was tested using Cronbach’s Alpha coefficient (>0.6). The questionnaire was administered to 31 outpatients at the Neurology Clinic of RSUD Arifin Achmad, Riau Province, and RSAU Dr. M. Salamun Bandung. Validity testing demonstrated that most correlation coefficients (r) between domains were acceptable (0.470–0.892) and statistically significant at p<0.01, except for item number twenty (r=0.345). Reliability testing showed a high overall Cronbach’s Alpha value of 0.924. Based on these findings, the Indonesian version of the PDQ-39 questionnaire is a valid and reliable instrument for measuring the quality of life in Parkinson's disease patients.Kuesioner PDQ-39 merupakan instrumen spesifik yang digunakan untuk mengukur kualitas hidup pasien Parkinson. Pengukuran kualitas hidup menjadi salah satu parameter dalam menilai keberhasilan terapi pada pasien yang menerima terapi farmakologi maupun nonfarmakologi. Kuesioner PDQ-39 telah digunakan secara luas di berbagai negara termasuk Indonesia. Namun, hingga saat ini belum ditemukan penelitian yang mempublikasikan kuesioner PDQ-39 versi Bahasa yang telah diuji validitas dan reliabilitasnya. Penelitian ini bertujuan untuk menguji validitas dan reliabilitas kuesioner PDQ-39 dalam versi Bahasa Indonesia. Penelitian menggunakan rancangan potong lintang dengan teknik pengambilan sampel secara konsekutif. Penelitian dimulai dengan proses adaptasi bahasa. Validitas kuesioner diuji dengan teknik korelasi Pearson Product Moment, sementara reliabilitas diuji menggunakan Cronbach’s Alpha (>0,6). Kuesioner diujikan pada 31 pasien rawat jalan di Poliklinik Saraf RSUD Arifin Achmad Provinsi Riau dan RSAU Dr. M. Salamun Bandung. Hasil uji validitas menunjukkan hampir semua koefisien korelasi (r) antar domain dapat diterima (0,470-0,892) dengan nilai signifikan pada p>0,01, kecuali pertanyaan nomor dua puluh (r=0,345). Nilai reliabilitas secara keseluruhan menunjukkan nilai Cronbach’s Alpha yang tinggi yaitu sebesar 0,924. Berdasarkan hasil penelitian dapat disimpulkan bahwa kuesioner PDQ-39 versi Bahasa Indonesia dinyatakan valid dan reliabel untuk mengukur kualitas hidup pasien Parkinson
Improving Young Athletes' Life Skills Through An Integrated Early Age Football Competition Model In The Framework Of Positive Youth Development
Full text linkThe background of this research is based on the importance of developing young
athletes, emphasizing not only technical sports skills but also character
development, social skills, and readiness to face life's challenges. This study aims
to analyze the effectiveness of an integrated competition model in improving the life
skills of young athletes as part of Positive Youth Development (PYD) efforts. The
research method used was a quasi-experimental design with a pretest-posttest
control group. The research subjects consisted of young athletes aged 12–16 years
with a total sample of 48 athletes (24 experimental; 24 control). The
average -pretest score of the experimental group was 142.8 ± 9.4 and increased in
the posttest to 147.1 ± 8.7 (Δ = +4.33). The control group increased from 141.9 ±
9.1 to 142.1 ± 8.5 (Δ = +0.17). The treatment effect showed a significant difference
(t = 8.29; p < 0.001) with a Cohen's d effect size of 1.69. The integrated competition
model resulted in the largest improvements in teamwork (20%) and communication
(18%). These findings confirm that combining competitive elements with life skills
learning structures is an effective strategy in supporting Positive Youth
Development.
Keywords: life skills, young athletes, integrated competition model, positive youth developmentLatar belakang penelitian ini berangkat dari pentingnya pembinaan atlet muda yang tidak hanya menekankan pada aspek keterampilan teknis olahraga, tetapi juga pada pengembangan karakter, keterampilan sosial, dan kesiapan menghadapi tantangan kehidupan. Penelitian ini bertujuan untuk menganalisis efektivitas model kompetisi terintegrasi dalam meningkatkan kecakapan hidup (life skills) atlet muda sebagai bagian dari upaya Positive Youth Development (PYD). Metode penelitian yang digunakan adalah eksperimen semu dengan desain pretest-posttest control group. Subjek penelitian terdiri atas atlet muda berusia 12–16 tahun dengan total sampel 48 atlet muda yang dibagi ke dalam kelompok eksperimen dan kelompok kontrol. Instrumen pengumpulan data mencakup angket kecakapan hidup, observasi, dan wawancara terstruktur. Analisis data dilakukan menggunakan uji paired sample t-test dan independent sample t-test untuk mengukur perbedaan signifikan antar kelompok. Hasil penelitian menunjukkan bahwa penerapan model kompetisi terintegrasi secara signifikan meningkatkan berbagai aspek kecakapan hidup, meliputi keterampilan komunikasi, kerja sama tim, pengendalian emosi, pengambilan keputusan, serta kepemimpinan, dibandingkan dengan model pembinaan konvensional (p < 0,05). Temuan ini mengindikasikan bahwa penggabungan aspek kompetitif dengan pembelajaran terstruktur dalam kompetisi mampu menjadi strategi efektif untuk mendukung pengembangan positif atlet muda, baik dalam konteks olahraga maupun kehidupan sehari-hari
Analysis of Characteristics, Bioeconomics, and Optimization of Sustainable Management of Largehead hairtail (Trichiurus Lepturus) Commodities in Coastal Waters of Pangandaran Regency
Full text linkLargehead hairtail (Trichiurus lepturus) is a potential fish commodity in the seawaters of Pangandaran Regency. Fishing activities operate under an open-access regime, allowing unrestricted participation. The lack of catch restrictions can lead to overfishing. This research aims to determine the optimal level of production, fishing effort, and economic rent, both in terms of biology and economics, to ensure sustainable management of largehead hairtail resources in Pangandaran Regency. The research method used is a case study that includes both primary and secondary data. Primary data were collected through direct interviews with government officials, stakeholders, and fishermen, while secondary data, in the form of capture fisheries statistics for 2018–2023, were obtained from Cikidang Fishing Port. The analysis employs biotechnical analysis, bioeconomics, and static optimization using the Gordon-Schaefer model for bioeconomic analysis. The results showed that the standard fishing gear was purse seine with an average CPUE (catch per unit effort) of 32.86 kg/trip. Biological parameter estimation resulted in an intrinsic growth rate (r) of 0.872 tons per year, a fishing gear coefficient (q) of 0.00012 tons per trip, and an environmental carrying capacity (K) of 277,083 tons. Largehead hairtail resources in Pangandaran have not yet reached overfishing. The utilization rate of largehead hairtail was 42.69% with a ‘develop’ status. The Maximum Economic Yield (MEY) management regime provides the largest economic rent of Rp549,802,899 per year, with a maximum fishing effort of 3,684 trips per year and a maximum catch of 80.35 tons per year
PENGEMBANGAN DESAIN INTERAKTIF SEBAGAI EDUKASI MITIGASI BENCANA TSUNAMI BERBASIS KEARIFAN LOKAL PADA KELURAHAN BARINGIN
Full text linkIndonesia is vulnerable to tsunami disasters due to its location on the Ring of Fire. Education on tsunami mitigation is extremely important, especially in high-risk areas like Kelurahan Baringin. Local wisdom can be a valuable source of knowledge for this education. Interactive design can be an effective medium for education. The objective of this research is to develop an interactive design for tsunami mitigation education based on local wisdom in Kelurahan Baringin to increase community knowledge and preparedness. The research method will employ a qualitative approach with a design research method. Data will be collected through observation, interviews, and focus group discussions. The outcome will be an interactive design that integrates local wisdom, providing information on tsunamis, mitigation, and local wisdom. The design will be packaged in an engaging and easy-to-understand animated video.Indonesia rawan bencana tsunami karena lokasinya di Ring of Fire. Edukasi mitigasi tsunami sangat penting, terutama di daerah berisiko tinggi seperti Kelurahan Baringin. Kearifan lokal dapat menjadi sumber pengetahuan berharga untuk edukasi ini. Desain interaktif dapat menjadi media edukasi yang efektif. Tujuan penelitian ini adalah mengembangkan desain interaktif edukasi mitigasi tsunami berbasis kearifan lokal di Kelurahan Baringin untuk meningkatkan pengetahuan dan kesiapsiagaan masyarakat. Metode penelitian akan menggunakan pendekatan kualitatif dengan metode desain research. Data akan dikumpulkan melalui observasi, wawancara, dan FGD. Hasil penelitian akan dirancang sebuah desain interaktif yang mengintegrasikan kearifan lokal, memuat informasi tentang tsunami, mitigasi tsunami, dan kearifan lokal terkait. Desain interaktif dikemas dalam bentuk video animasi yang menarik dan mudah dipahami
ANALYSIS OF COMMUNITY SATISFACTION INDEX (CSI) IN THE SOCIAL PROJECT: IMPLEMENTATION OF GOOD AGRICULTURAL PRACTICE (GAP) TO ENHANCE HIGH-LYCOPENE TOMATO CULTIVATION
Full text linkThis study aims to evaluate the Community Satisfaction Index (CSI) associated with the implementation of Good Agricultural Practice (GAP) in enhancing high-lycopene tomato cultivation. Employing a quantitative survey design, the research assessed participant satisfaction across nine core components, including program requirements, procedures, service delivery, costs, staff competence, and infrastructure support. The results indicate a generally high level of satisfaction, with the overall CSI reaching 92.06, which classifies the program performance as “very good.” Among the assessed components, the Competence of Program Staff received the highest rating, reflecting the vital role of knowledgeable facilitators in ensuring program success. While most components were positively evaluated, facilities and infrastructure emerged as areas requiring further development to enhance long-term sustainability. The use of simple yet impactful technologies, coupled with clear communication and open knowledge-sharing sessions, contributed to the program’s positive reception. These findings suggest that the program was well-accepted by the community and is considered feasible for continuation and potential expansion in similar agricultural contexts
Evaluating Policy Environment for Community-based Rural Tourism: Multi-Actor Perspectives in Tourism Value Chain
Full text linkTourism policies are essential in the development of community-based rural tourism (CBRT). In practice, their implementation requires a favorable policy environment. However, the CBRT literature has not investigated the policy environment and the holistic interactions between government-community relations, inter-agency coordination, and other complex challenges relevant to CBRT policies. Involving multiple CBRT actors, this study aimed to evaluate the policy environment in the development, implementation, and evaluation of CBRT-related policies. Using Tourism Value Chain (TVC) as the conceptual framework and considering the aspects of Tourism Value Webs (TVW), this research employed qualitative interviews with government officers. In addition, this study included archival research on policy documents and questionnaire surveys among community members in multiple case studies as an added triangulation. The case studies involved 49 tourism villages in Sleman Regency, Yogyakarta, Indonesia. The regency has embraced the community-based tourism (CBT) concept for rural development by creating tourism villages. Multiple institutions in the regency work with academia and the business sector in support of the communities in developing tourism villages, forming a multiple helix structure. Despite some limitations in the policy documents, the main stakeholders in Sleman Regency can organically coordinate and cooperate to take care of all TVC phases, implying their commitment and consciousness to achieve self-reliance in CBRT development. These findings imply that the policy environment for CBRT policies is dynamic. It thus requires all stakeholders to conduct a more proactive and adaptive approach to policy evaluation, enabling enhanced support for the long-term success and sustainability of CBRT initiatives
Discretization and Associated Asymptotic Behavior for the Lax Equation with Skew-symmetry
Full text linkThe computation of matrix eigenvalues is vital for understanding various scientific phenomena. The QR method, which is based on the QR factorization of a matrix, is a common approach in numerical linear algebra. In integrable systems, the one-step process of the QR method is related to the time evolution of the Lax equation. In this paper, we clarify the relationship between the QR method, which incorporates an origin shift parameter, and the Lax equation with skew-symmetry. Furthermore, we show the asymptotic convergence of discretization based on matrix factorization of the Lax equation with skew-symmetry as discrete time approaches infinity
Kajian Penentuan Modulus Elastisitas Baja dan Aluminium dengan Metoda Ultrasonic Pitch & Catch
Full text linkModulus elastisitas adalah salah satu sifat material yang menyatakan nilai kekakuan dari material tersebut. Modulus elastisitas menunjukkan kemampuan material untuk menahan deformasi elastis saat diberi tegangan, yang mencerminkan hubungan antara tegangan dan regangan dalam batas elastisitas material tersebut. Metoda paling umum untuk menentukan nilai modulus elastisitas adalah dengan uji tarik tetapi masih mempunyai kekurangan harus merusak benda uji. Metoda uji tidak rusak yang dapat digunakan untuk menentukan nilai modulus elastisitas salah satunya adalah dengan menggunakan uji ultrasonik. Penentuan nilai modulus elastisitas dengan metoda ultrasonik pada material logam sudah dilakukan sebelumnya namun belum dapat menentukan nilai modulus elastisitas pada material pipa atau pada material dengan permukaan yang luas. Penelitian ini bertujuan mengkaji penentuan nilai modulus elastisitas pada material baja dan aluminium dengan metoda ultrasonik pitch & catch dengan variasi formula, variasi frekuensi probe dan variasi tebal benda uji. Validasi hasil uji dilakukan dengan membandingkan modulus elastisitas hasil metoda ultrasonik pitch & catch dengan modulus elastisitas dari referensi. Hasil penelitian menunjukkan bahwa variasi frekuensi probe, jarak antar probe dan tebal benda uji diatas 5mm menghasilkan nilai modulus elastisitas yang sesuai dengan referensi. Tebal benda uji dibawah 5mm menjadi batasan dari metoda ultrasonik pitch & catch dalam menentukan nilai modulus elastisitas karena data kecepatan gelombang longitudinal tidak akurat pada material yang tipis