Judul: Effects of LED (Light-Emitting-Diode) Spectrum and Intensity on Strawberry (Fragaria x ananassa Duch.) Plant Physiology and Secondary Metabolite Profiles in Lowlands
Abstrak: Stroberi (Fragaria x ananassa Duch.) merupakan tanaman asal iklim subtropis yang dapat dibudidayakan di daerah beriklim tropis. Upaya penyeseuaian lingkungan tumbuh asal tanaman dapat dilakukan dengan penggunaan LED sebagai cahaya buatan. Penelitian bertujuan mengetahui respons fisiologi dan karakterisasi metabolit sekunder terhadap stroberi yang diberikan perlakuan LED. Penelitian menggunakan rancangan kelompok lengkap teracak (RKLT) yang terdiri atas 2 faktor yaitu spektrum dan intensitas cahaya. Faktor spektrum terdiri atas 6 taraf yaitu merah 100%, biru 100%, merah 75% biru 25%, merah 25% biru 75%, merah 50% biru 50%, dan putih 100%. Faktor intensitas teridiri dari atas 2 taraf yaitu intensitas 3 strip dan intensitas 5 strip. Penelitian dilakukan dengan 3 ulangan yang masing-masing terdapat 6 satuan percobaan. Berdasarkan hasil penelitian diketahui bahwa LED spektrum biru 5 strip dan kombinasi merah 25% biru 75% 3 strip dapat mempercepat pertumbuhan pucuk tanaman stroberi. Spektrum kombinasi cahaya merah 25% biru 75% dengan intensitas 5 strip lebih baik dalam mengakumulasikan klorofil dibanding perlakuan lainnya. Spektrum dan intensitas LED tidak memberikan pengaruh yang signifikan terhadap kandungan glukosa daun. Penggunaan cahaya putih 5 strip dapat meningkatkan akumulasi fruktosa daun. Penelitian metabolit sekunder daun menunjukkan ada 4 senyawa umum yang ada pada semua perlakuan. Setiap kombinasi perlakuan spektrum dan intensitas memiliki minimal 1 senyawa spesifik hasil metabolit sekunder kecuali perlakuan merah 50% biru 50% 3 strip., Strawberry (Fragaria x ananassa Duch.) is a plant originated from subtropical areas and can be cultivated in tropical areas. Efforts to adapt the growing environment from plant origin can be done by using LEDs as artificial light. This study aims to determine the physiological response of strawberry plants given LED treatment. The study used a complete randomized block design (RBD) which consisted of 2 treatments, namely light spectrum and intensity. Spectrum factor consists of 6 levels, 100% red, 100% blue, 75% red 25% blue, 25% red 25% blue 75%, 50% red 50% blue, and 100% white. The intensity factor consists of 2 levels, 3 strips and 5 strips. The research was conducted with 6 sample and 3 replicate. The study shows the use of 5 strips blue spectrum LED and 3 strips combination of 25% red 75% blue LED can accelerate shoot growth in strawberry. The combination of 5 strips 25% red 75% blue LED treatment is better on accumulate chlorophyll then other treatment. The spectrum and intensity of the LED did not give a significant effect on leaf glucose levels. The use of 5 strips white LED can increase the amount of fructose in the leaves. Research on profiling secondary metabolites shows that strawberry leaves produced 4 common compounds present in all treatments. Each combination of spectrum and intensity treatment has at least 1 specific compound resulting from secondary metabolites except the 50% red 50% blue 3 strips treatment.
Keyword: buah subtropis, cahaya, gula, klorofil, kromatografi, chlorophyll, chromatography, lights, subtropical fruits, sugar content

Judul: Effects of Spectrum and Ilumination Time of Light Emitting Diode (LED) on Physiology and Secondary Metabolite Profiles of Strawberries in Lowlands
Abstrak: Stroberi sebagai buah dengan antioksidan tinggi memiliki perbedaan fisiologi dan metabolit sekunder yang bergantung dengan teknik budidayanya. Salah satu perlakuan modifikasi lingkungan yang dapat dilakukan adalah penggunaan LED sebagai cahaya buatan. Penelitian bertujuan mengetahui jenis cahaya dan waktu penyinaran LED terhadap fisiologi dan metabolomik stroberi. Penelitian menggunakan rancangan acak kelompok (RAK) dengan dua faktor berupa jenis cahaya LED (biru, merah, kombinasi merah-biru dan putih) dan waktu penyinaran (15 jam, 18 jam dan 21 jam). Hasil penelitian menunjukkan bahwa LED biru 18 jam memiliki efektivitas dalam meningkatkan pertumbuhan pucuk. Penggunaan LED kombinasi dengan waktu penyinaran 15 jam dan 21 jam memiliki hasil terbaik dalam akumulasi klorofil, glukosa dan fruktosa. Senyawa metabolit umum yang ditemukan berupa, tyrasol, phytol, asam linoleat, asam palimtat, vitamin E dan clionasterol. Senyawa spesifik banyak ditemukan di perlakuan kontrol dan LED merah., Strawberries are a fruit with high antioxidants, have differences in physiology and secondary metabolite profiles that depend on their cultivation technique. One of the cultivation technique treatments is the use of LEDs as artificial light. This research was aimed to determine the type of light and photoperiod that can optimize the physiology and metabolomics of strawberries using LEDs. The study used a randomized block design (RBD) with two factors, the type of LED light (blue, red, combination of red-light, and White) and photoperiod (15 hours, 18 hours, and 21 hours). The results showed that the 18 hours blue LED was effective in increasing shoot growth. The combination of LED uses with 15 hours and 21 hours has the best results in the accumulation of chlorophyll, glucose, and fructose. Common metabolite compounds found are tyrasol, phytol, linoleic acid, palmitic acid, vitamin E and clionasterol. Specific compounds were found in the control and red LED treatments.
Keyword: chlorophyll, glucose, LEDs, secondary metabolite, strawberry

Judul: Penyelesaian Masalah Rotasi Aliran Fluida Kental Von Karman Menggunakan Metode Homotopi
Abstrak: Von Karman equation is an equation that describes fluid viscous flow induced by infinite disk rotation. By assuming steady flow and laminar, viscous incompressible fluid flow is represented in Von Karman equation by an angular velocity and the vertical direction velocity as the independent variables. Von Karman equation is a nonlinear problem that is solved using the homotopy method. The use of homotopy method is done by defining an homotopy function that requires auxiliary parameters to control the convergent region of the solution. The solution is a recursive formula with given initial conditions. Using software based-functional shows that velocity components converge to a value.
Keyword: