PEMBUATAN ALAT UKUR ABSORPSI SUARA BERDASARKAN KOEFISIEN TRANSMISI DENGAN METODE TABUNG IMPEDANSI BERBASIS MIKROKONTROLER ATMEGA328

Penelitian pengukuran karakteristik penyerapan suara merupakan hal yang penting dalam menentukan material yang dapat digunakan sebagai peredam kebisingan. Pada penelitian ini telah dilakukan pembuatan alat ukur, eksperimen dan simulasi mikrokontroler untuk pengukuran koefisien absorpsi suara berdasarkan koefisien transmisi dengan menggunakan metode tabung impedansi. Pada penelitian ini digunakan material rockwool dan diperoleh nilai koefisien absorpsi suara yang bervariasi terhadap perbedaan ketebalan material, yaitu 1 cm, 2,5 cm dan 5 cm serta variasi frekuensi 300 Hz, 400Hz, 500Hz, 1000 Hz dan 2000 Hz. Nilai koefisien absorpsi tertinggi diperoleh pada material dengan ketebalan 2,5 cm pada frekuensi 1000 Hz yaitu 0,996 dan koefisien absorpsi paling rendah pada material dengan ketebalan 1 dan 2,5 cm pada frekuensi 300 Hz yaitu 0,045. Dari penelitian ini diketahui bahwa pengukuran koefisien absorpsi dengan menggunakan koefisien transmisi dapat dijadikan penentuan nilai koefisien absorpsi suara namun masih kurang efektif. Dari penelitian ini juga diketahui bahwa nilai koefisien absorpsi suara yang diperoleh kurang memenuhi nilai standar yang ada dalam referensi sehingga diharapkan dapat dikembangkan alat pengukuran tanpa simulasi yang lebih akurat dalam pengukuran absorpsi suara dari suatu material. Research on measuring sound absorption characteristics is important in determining the material that can be used as a noise absorber. In this research, experiments and simulations microcontroller for the measurement of sound absorption coefficient have been carried out based on the transmission coefficient using the impedance tube method. In this study using materials rockwool, and the value of the sound coefficient varies with differences in material thickness, namely 1 cm, 2.5 cm and 5 cm and the frequency variations of 300 Hz, 400Hz, 500Hz, 1000 Hz and 2000 Hz. The highest coefficient value is obtained in material with a thickness of 2.5 cm at a frequency of 1000 Hz, which is 0.996 and the lowest absorption coefficient on a material with a thickness of 1 and 2.5 cm at a frequency of 300 Hz, which is 0.045. From this research, it is known that the measurement of absorption coefficient by using the transmission coefficient can be used to determine the value of the sound absorption coefficient, but it is still less effective. From this study it is also known that the value of the sound absorption coefficient obtained does not meet the standard values that exist in the reference so that it is expected to develop measurement tools without a more accurate simulation in measuring the sound absorption of a material

HUBUNGAN MUSIC-BASED MOOD REGULATION DENGAN SUBJECTIVE-WELL BEING PADA MAHASISWA

Penelitian ini dilakukan untuk melihat hubungan antara Music-Based Mood Regulation dengan Subjective Well-Being pada Mahasiswa. Pendekatan kuantitatif dengan metode korelasi digunakan dalam penelitian ini. Partisipan yang terlibat dalam penelitian ini sebanyak 526 mahasiswa yang berada pada rentang usia 18-24 tahun menggunakan Brief Music-based Mood Regulation Scale (MMRS) untuk mengukur music-based mood regulation, Satisfaction With Life Scale (SWLS) yang mengukur dimensi kognitif subjective-well being dan Scale of Positive and Negative Experience dimensi afektf subjective-well being. Hasil uji hipotesis menggunakan uji korelasi menunjukan bahwa tidak ditemukan hubungan antara music-based mood regulation dengan subjective well-being.----------This research was conducted to examine the correlation between Music-Based Mood Regulation and Subjective Well-Being in College Students. Quantitative approach was used in this research. 526 university students aged between 18-24 years old participated in this research. Researcher used questionairre to gather data using Brief Music-based Mood Regulation Scale (MMRS) (Saarikallio,2012), Satisfaction With Life Scale (SWLS) (Diener, Emmons, Larsen, & Griffin, 1985) dan Scale of Positive and Negative Experience (SPANE,2009). The result indicated that there are no correlation between music-based mood regulation dengan subjective well-bein

Synthesis of Zn-Fe nanoparticles using pulse laser ablation as a contrast agent in magnetic resonance imaging

Synthesis of zinc oxide nanoparticles, iron oxide nanoparticles and Zn-Fe nanoparticles using pulse laser ablation method has been conducted. Experimentally, a pulse Nd:YAG laser (1064 nm, 7 ns, 35 mJ) was directed and focused on a metal plates of pure Zn and Fe, which are placed in the liquid medium of polyvinyl pyrrolidone (PVP). The PVP functions as a stabilizer agent. The results show that the produced nanoparticles have a spherical shape with an averaged diameter of Zn-Fe nanoparticles of 13 nm. FTIR and XRD test results of Zn-Fe nanoparticles show characteristics of Zn-Fe compounds. The examination of Zn-Fe nanoparticles as MRI contrast agents was carried out by varying the concentration of nanoparticles. Cenh calculation results showed the highest contrast enhancement occurred at a concentration of 1.25 mM with a value of 64.26% for T1 weighted images, and 81.52% for T2 weighted images. The SNR calculation results show the highest value at a concentration of 1.25 mM of 70.52 for T1 weighted images. The highest SNR value in the T2 weighted image at a concentration of 0.156 mM of 165.09

Effect Of Microwave In The Green Synthesis Of Colloidal Bismuth Nanoparticles

In this study, bismuth nanoparticles were synthesized and prepared using citrus aurantifolia green synthesis method. The effect of microwave heating was examined. Citrus aurantifolia was used to reduce metal ions and nanoparticle formation due to the presence of various biomolecules needed. microwave was chosen because it can accelerate and form more stable nanoparticles. Bismuth nanoparticles were successfully synthesized with UV-Vis wavelength at 276 nm and nanoparticle average size is 4.66 nm. This result also shows a better TEM result image when with microwave because there is no impurity from bioreductor

Penghitungan Rasio Intensitas Ca (II) 396,8 nm dan Ca (I) 422,6 nm pada Sampel Tasbih Asli dan Imitasi menggunakan Metode Laser Induced Shock wave plasma (LISPS)

Spectral analysis of elemental bead samples has been done using Laser Induced Schock Wave Plasma(LISPS). This experiment is aim to distinguish between bead samples from fresh white coral and its artificial from hardwood through determination of spectral intensity of Ca(II) 396,8 nm and Ca(I) 422,6 nm. The samples are held by 10 torr and induced by NdYAG Laser 1064 nm in wavelength. Results show that the original and artificial samples can be distinguished from ratio of intensity at 1,68 : 0,80 both for white coral and its artificial from hardwood through determination of spectral intensity of Ca (II) 396,8 nm dan Ca (I) 422,6 nm respectively

Zinc Oxide Nanoparticles (ZnONPs) Photocatalyst using Pulse Laser Ablation Method for Antibacterial in Water Polluted

Synthesis of zinc oxide nanoparticles by pulse laser ablation method has been successed carried out. Synthesis was carried out in aquades medium with a repetition rate variation of 5 Hz, 10 Hz and 15 Hz pulse laser yielding brown colloids. The higher laser repetition rate, the colloidal color will be more dark brown. Characterization of zinc oxide nanoparticles includes UV-Vis, SEM-EDX, FTIR and XRD. The image of SEM shows that zinc oxide nanoparticles have a round shape. Measurement of particle distribution with imageJ software from SEM images showed that ZnO nanoparticles were 23.63 nm, 12.13 nm and 5.59 nm for 5 Hz, 10 Hz and 15 Hz shots. The EDX spectrum analysis results show that only Zn and O atoms in the ZnO nanoparticles colloid are synthesized. FTIR results showed that sprocket ZnO was formed at wave number 457 cm-1 and 545 cm-1. The XRD analysis results also show some peaks known as the ZnO phase. This indicates that ZnO nanoparticles have been formed. The testing of the antibacterial activity of ZnO nanoparticles using a liquid dilution method with nanoparticle concentrations of 40 ppm, 60 ppm and 80 ppm. The test results showed the percentage of degradation of Escherichia coli bacteria at concentrations of 40 ppm, 60 ppm and 80 ppm respectively at 89.60%, 97.76% and 98, 70%

Identification Of Java Agate Elements Using Libs Methods

Agate is a stone that is created due to natural processes from the deposition of fossils and the formation of minerals that combine to become an agate. In essence, agate contains elements contained therein. The content of these elements can be used to distinguish the type of agate. Several methods are used to detect the elemental content of agate, including X-Ray Fluorescence and X-Ray Diffraction methods. In this study, agate will be tested using the LIBS method. The LIBS method is an alternative and effective method for identifying elements from a sample because this method does not require the sample to receive special treatment. Laser plasma optimization is done by varying the laser energy. The higher the value of the laser energy given, the intensity of the elemental spectrum will be higher. The results of the LIBS method show compatibility with the XRF method as a comparative study. The results showed that the elements contained in the agate are the elements Al, Mn, Si, Fe, Mg, Na, and Ca

Rapid Detection Of Heavy Metals On Waste-Water Polluted Soils Using Laser Induced Breakdown Spectroscopy

The Laser Induced Breakdown Spectroscopy (LIBS) method was successfully used to detect heavy metal elements in the soil polluted by wastewater from paper mills. The study was conducted using a Nd: YAG pulse laser with a wavelength of 532 nm at 83 mJ energy and 5 torr air pressure. The laser is fired at a soil sample that has been made in the form of pellets to produce plasma. The plasma emission spectrum formed is then detected by multichannel analyzer (OMA) to obtain the emission line spectrum that represents the content of atoms and molecules in the soil sample. The spectrum detected by OMA is then compared to the standard reference spectrum at NIST (National Institute of Standards and Technology) to find out the contents of an element on a contaminated soil sample. several types of heavy metal elements Fe, Cr, Cu, Al, Cd and Mn in soils contaminated by wastewater were detected using LIBS method. Based on research results, the LIBS method is very well used for the detection of heavy metal content in polluted soils

ANALISIS DYADIC RELATIONSHIP MAINTENANCE BEHAVIOR PADA PASANGAN YANG MENJALANI HUBUNGAN PERNIKAHAN JARAK JAUH

Penelitian ini bertujuan untuk mengetahui noninependensi relationship maintenance behavior pada pasangan suami istri yang menjalani hubungan jarak jauh. Partisipan terdiri dari 52 pasangan. Data diambil dengan teknik snowball sampling. Relationship maintenance behavior diukur dengan skala Relational Maintenance Behavior Measure (RMBM) dari Stafford (2011). Teknik analisis yang digunakan adalah dyadic analysis. Hasil analisis menunjukkan adanya nonindependensi relationship maintenance behavior pada pasangan suami istri yang menjalani hubungan jarak jauh. Dengan demikian, dapat disimpulkan adanya saling ketergantungan dan kesamaan perilaku relationship maintenance behavior pada pasangan yang menjalani hubungan jarak jauh.