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"Flotation is animportant process in mining industries. This process employs the bubble andhydrophobic properties of a particle to separate valuable mining particles fromimpurities. The most important phenomenon in determining flotation efficiencyis the bubble-particle interaction; therefore, understanding this phenomenon isvery important. The aim of this research is to study the mechanism ofbubble-particle interactions with and without the addition of a collector. Theexperimental setup consists of a water container, bubble generator, particlefeeding system, and an image capturing system. The water container is made fromtransparent material of a size large enough so that the wall?s effects onbubbles and particles can be neglected. Air bubbles are generated by a bubblegenerator which consists of a small nozzle and programmable syringe pump. Ahigh speed video camera and halogen lamp backlighting system are used as imagecapturing devices. Observation of the images reveals that bubble-particleinteraction follows the stages of bubble-particle collision, particle attachedto the bubble, and particle detached from the bubble. The addition of acollector to the liquid affects the bubble-particle interactions."

"Dengan semakin berkembangnya teknologi informasi, profil suatu komunitas/lembaga menjadi bagian tak terpisahkan untuk menyatakan eksistensi komunitas/lembaga tersebut. Tak terkecuali pada remaja yang aktif di berbagai komunitas. Pada kalangan remaja, profil komunitas berbentuk video menjadi alatyang disukai karena pembuatannya yang lebih mudah dan bersifat dinamis. Pembuatan video pendek untuk menyatakan profil komunitas siswa SMU membutuhkan teknik editing video. Dalam program pengabdian masyarakat ini, pengabdi memberikan pelatihan dan pendampingan pada siswa SMA Bopkri 2 Yogya untuk membuat profil komunitas mereka. Pelatihan diikuti oleh 31 siswa kelas 10 dan 11, yang mayoritas merupakan peserta ekstra kurikuler fotografi. Siswa dibagi menjadi 6 kelompok. Materi pelatihan meliputi penjelasan tentang berbagai jenis profil, penggunaan alat dan teknik perekaman video, editing video.Pada pertemuan terakhir, siswa diminta untuk mempresentasikan hasil video yang telah dibuat. Hasil akhir berupa 5 buah video profil komunitas yang diunggah ke media sosial youtube. Kendala yang dihadapi adalah ketersediaan alat pendukung. Beberapa siswa tidak mempunyai laptop dan alat perekam dengan spesifikasi yang memadai sehingga kualitas hasil video kurang maksimal."

"Wireless 3.5G is designed to deliver various kind of multimedia packages through IP network. Quality of Service (QoS) fulfilment is a crucial factor for multimedia applications...."

"The presentstudy investigated the mechanical properties and microstructure of ultrafinegrained (UFG) brass processed by four passes of equal channel angular pressing(ECAP) and annealed at elevated temperatures. The mechanical properties of allsamples were assessed using tensile and micro-hardness tests. Microstructureanalysis was performed using optical microscopy (OM) and scanning electronmicroscopy (SEM). Ultimate tensile strengths (UTS) and yield strengths (YS) of878 and 804 MPa, respectively, ductility of 15%, and hardness of 248 HV wereobtained for samples processed by four passes of ECAP with equivalent truestrain of 4.20. Annealing at 300°C caused UTS and YS to decrease significantly,to 510 and 408 MPa, respectively, ductility to increase to 28%, and hardness todecrease to 165 HV. Fractography analysis of un-annealed samples after fourECAP passes showed small brittle fractures with shallow dimpling. Ductilefailures were found on annealed samples. After four ECAP passes, themicrostructure of un-annealed samples was UFG and dominated by lamellar grainwith shear band. In contrast, after annealing, the microstructure changed dueto recrystallization, showing nucleation and grain growth."

"The definition of the physical and mechanicalproperties of sugarcane trash pellets were necessary for the designconsiderations relating to storage, handling andprocessing equipment. The mixing ratios of groundsugarcane trash:cassava starch:water content (1.0:0.25:0.85 and 1.0:0.25:1.40 by weight) and pelleting speeds (100, 120, 140, and 160 rpm) were considered to determine their effects on bulkdensity, true density, porosity, durability and compressive strength. The results show that the mixing ratio byweight of 1.0:0.25:0.85 and pelleting speed of 120to 140 rpm were optimum for producing the sugarcane trash pellets. At the moisture content of 12.01% (wb), the bulk density, true density, durability and compressive strengthof biomass pellets were in the range of 330.93 to 365.00 kg/m3, 860.38 to 918.43 kg/m3, 99.34 to 99.46 % and 5.15 to 6.43 MPa, respectively."

"Agricultural waste hasincreased colossally with development in agricultural production causing environmentalnuisance and degradation. Utilization of coconut husks, one of such type of waste, as a biosorbent for polluted surface water treatment, wasconsidered in this study. Polluted surface water was gently passed through twosimilar columns loaded with 100 and 200 g of coconut husk char respectively.The treated water samples collected after 30, 60, 90, 120 and 150 mins wereexamined for SO42-, NO3- and PO43-ions concentration. Removal efficiency for SO42-, NO3-and PO43- ions on 100 g coconut husk char after 150mins detention time were 70, 78 and 91% respectively. Freundlich isotherm modelgave a better description of the data (R2 > 0.96). Sorption datawas well described by second order pseudo kinetics (R2 >0.85). An amount of 100 g of the biosorbenthas astrong affinity for these types of ion removal in contaminated water. Coconut huskchar as a biosorbentis a panacea to significant concentrations of polyatomic ions in polluted surface water."

"ABSTRAKPerkembangan teknologi dan transformasi sosial-ekonomi telah menyebabkan bisnis jaringan seluler 5G mengalami perubahan, sehingga jaringan seluler 5G diharapkan dapat mengirim informasi dengan cepat dan mendukung kasus penggunaan yang banyak bermunculan dari berbagai aplikasi. Salah satu kasus penggunaan pada jaringan 5G adalah massive Machine Type Communication (MTC). Salah satu aplikasi massive MTC adalah jaringan sensor nirkabel (JSN). Tantangan bagi jaringan seluler 5G ini adalah bagaimana memodelkan arsitektur/topologi untuk mendukung JSN dan bagaimana mengatasi masalah efisiensi konsumsi energi di JSN. Untuk menjawab tantangan ini, maka diterapkan sistem HAP yang terintegrasi JSN dan menggunakan protokol routing Low Energy Adaptive Clustering Hierarchy. Sistem HAP dirancang untuk digunakan di ketinggian 20 km dengan topologi tanpa dan dengan clustering, menggunakan 1.000 node sensor. Sistem ini telah disimulasikan dengan menggunakan MATLAB. Simulasi dilakukan untuk melihat konsumsi energi, jumlah node yang mati dan rata-rata total paket yang dikirim ke HAP untuk topologi tanpa dan dengan clustering. Dari serangkaian simulasi, terlihat bahwa topologi dengan clustering dapat mengurangi konsumsi energi dan jumlah node yang mati, sekaligus meningkatkan total paket yang dikirimkan ke HAP."

"Barium strontium titanate (BST) or Ba1-xSrxTiO3 with x=0-1 possesses superior dielectric properties, which are widely used in many applications like in communication technology, electronic instrumentations, and various electrical devices. In this paper, the characterization of the particle and crystallite size of Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) is described. A two-step refinement commenced: first by mechanical milling, and then a further refinement under ultrasonic irradiation in a high power sonicator was applied to Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) particles. The crystalline powders were obtained through mechanically alloyed standard research grade BaCO3, TiO2, and SrCO3 precursors in a planetary ball mill.The powders were first found heavily deformed after 60 hours of milling and then went through a sintering process at 1200°C for 4 hours to form multicrystallite particles. The presence of a single phase in the three samples was solidly confirmed in their respective X-ray diffraction (XRD) patterns. The changes of multicrystallite particles into monocrystallite particles were obtained only after crystalline powders were irradiated ultrasonically in a high power sonicator. The processing variable during ultrasonic irradiation was limited to the duration time of irradiation and particle concentration in the exposed media. It is shown that the average sizes of BST particles at x=0; 0.3; 0.7 before ultrasonic irradiation were 353, 348, and 385 nm, respectively. These respective sizes decreased drastically to 52, 35, and 49 nm, respectively, after 12 hours of ultrasonic irradiation. These particle sizes are almost identical with that of their crystallite size. Hence, the synthesis of monocrystallite particles has been achieved. As the particle concentration of media takes effect, it is shown that an exposed media with a higher particle concentration tends to form multicrystallite particles."

"Todevelop seismic design criteria for buildings, seismic hazard analysis is required to estimate the ground motionintensity with criteria such as peak groundacceleration (PGA). The seismic hazard can be analyzed by using two approaches: deterministic seismic hazard analysis (DSHA) andprobabilistic seismic hazard analysis (PSHA). In these two approaches, theseismic hazard is evaluated from past earthquake events and active faults data. In Thailand, seismic hazard is classified in the low lying regions; however, in recently years,earthquakes have occurred frequently in the North of Thailand. Toprevent and reduce damage due to earthquakes in the future, determinationof seismic hazard is needed. Thisresearch proposes a deterministic seismic hazardmap evaluated from nineteenactive faults affectingThailand. Two types of active faults are considered: first, an active fault in a subduction zone and second, a crustal fault. The seismic hazard is evaluated by using a groundmotion prediction equation (GMPEs). Four GMPEs are weighted equally forseismic crustal fault, and two GMPEs are weighted equally fora seismic subduction zone. The hypocentral distance isused to evaluate the seismic hazard for all ground motion prediction equations.The Northern part and the Western part of Thailand are high seismic hazardregions, because there are active faults with the large possibility of earthquakes of a maximum magnitude. The seismichazards in the North, West and Northeast of Thailand are about 0.60 g.The seismic hazard in Bangkok is about 0.25 g due to the Three Pagoda fault and Sri Sawat fault. The seismic hazard in the South of Thailand is about 0.40 g."

"The antimicrobial properties of bagasse paper sheets coated withnatural polymers (chitosan, different ratios of (gelatin/glycerol) + chitosan,hemicellulose, hemicellulose + glycerol, hemicellulose+chitosan) orsynthetic organophosphorus dimer compounds were evaluated in this work.Hemicelluloses showed moderate activity against Bacillus subtilis and Candida albicans, while chitosan showed weakactivity against B. subtilis. The condition that offered the highest inhibitoryactivity of bagasse paper was the onecoated with 1,3-diaryl-2,2,2,4,4,4-hexachlorocyclodiphosph(V)azane(where aryl is p-chloroaniline or p-anisidine). The developed bagasse paperswere evaluated against Gram-positive bacteria, Gram-negative bacteria, yeasts, and fungi. The highest inhibitory activity was obtained at a concentration of 200mg/mL for p-chloroaniline with an inhibition zone that varied for differentmicrobes from 6.9 mm to 26 mm. The highest inhibitory activity was obtained at300?250 mg/mL for p-anisidine against most of the pathogenic microorganismswith an inhibition zone that varied for different microbes from 8 mm to 14.75mm. The observed antimicrobial and antifungal activity properties for bagasse paper coated with 1,3-diaryl2,2,2,4,4,4-hexachlorocyclodiphosph(V)azane could be attributed to the presence of Cl, P atoms, and the lone pair ofelectrons on N atoms in the structure of the dimers."