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Deteksi bawah air menggunakan teknologi akustik kelautan merupakan bagian dari metode penginderaan jauh. Hal ini disebabkan karena gelombang akustik mampu merambat di dalam air dengan baik. Salah satu faktor penting dalam pendeteksian dengan metode akustik adalah transduser sebagai Source Level pada sebuah sonar aktif. Metode penelitian dilakukan dengan membuat desain simulasi beamforming mengunakan aplikasi sensor array analyzer pada Matlab 2018 untuk menghasilkan parameter transduser dengan mode array. Parameter yang dihasilkan dari hasil simulasi digunakan sebagai referensi pembuatan transduser piezoelektrik (PZT). Prototipe transduser diberi sinyal trigger berupa beberapa ping atau burst dari sebuah driver akustik dan selanjutnya dilaksanakan uji coba memancarkan sinyal untuk mendeteksi target bawah air. Data echo yang direkam kemudian dilakukan pemrosesan sinyal sehingga hasil-hasil akhir prototipe sonar aktif mampu menghasilkan beamforming dengan beamdwidth 23,87 pada frekuensi 58,5 kHz, dengan Source Level (SL) sebesar 157,81 dB. Instrumen telah berhasil mendeteksi target argo float di kolom air dengan berbagai sudut yang berbeda. Nilai hasil deteksi Target Strength argo float maksimal sebesar –7,9 dB pada sudut 90 dan minimum sebesar –19,8 dB pada sudut 0.

Iodine deficiency disorder (IDD) is the most single common cause of preventable mental retardation and brain damage in the world. It decreases child survival, causes goiters, and impairs growth and development. Apuan Village, Bangli Regency is categorized as endemic areas (TGR=20,3%) according to the definition from Health Office reports of Bali Province in 2008. One of the approaches that might be worth considering in alleviating the problem is the empowerment of elementary school children in an effort to increase the consumption of iodized salt in household. This approach aimed at empowering children to provide information to their parents on iodized salt consumption. Community services activities were conducted from December 16 to 21 October 2010 in SD 1 and SD 3 Apuan involving 62 elementary school children. The main activities were the provision of knowledge and guidance to elementary school children about the benefits of iodized salt. The first phase of the activities consists of examining the level of iodine in salt. This phase was then followed by giving the students a pre-test prior to the guidance and a post-test after the guidance for measuring the level of improvement on knowledge of elementary school children about iodized salt. The second phase was conducted one week after the first phase by measuring the level of iodine in the household salt of the same respondents. Data were analyzed using descriptive and analytical by computer program. Results pre-test and post-tests showed an increase in the knowledge for good knowledge category (0% to 31%), and moderate knowledge category (3.2% to 40.3%) and while a decrease in the limited knowledge category (96.8% to 9.7%). Statistical analysis showed significant differences (p

Electrical transport across pulsed laser deposited zinc oxide (ZnO)/aluminum nitride (AlN)/Si(100) thin film structures has been studied using conducting atomic force microscopy. Current versus voltage spectroscopy performed on the samples with varying AlN layer thickness (t), revealed asymmetric nonlinear behavior with a finite zero current region. The effective barrier height of the system is found to be (∼0.2 eV). The width of the zero current region was found to decrease exponentially with respect to t finally attaining the bulk band gap value. Density functional theory based calculations were carried out on the AlN and AlN-ZnO composite surface to investigate the band gap variation and ZnO adsorption on AlN. Results obtained by these calculations are in harmony with the experimental findings. Calculated values of the bulk cohesive energy explain the growth of the ZnO in an axis perpendicular to the surface supporting the experimentally observed results. Constant voltage current scans studies on the same sample showed the existence of current leakage spots. Current scans performed with varying bias voltages described an unambiguous growth profile of current leakage spots. These leakage spots were observed to evolve in a self similar pattern with the bias, which implied a possible existence of fractal dimension in the pattern of their growth. Mass fractal analysis is therefore carried out to model the growth pattern. Evolution of the mass-fractal with respect to the applied bias is found to be a case of Rayleigh distribution on a two-dimensional Poisson field, in the limiting case. [ABSTRACT FROM AUTHOR]

Pulsed laser deposition technique was used for growing thin films of ZnO on Si (100) substrate held at different temperatures (Ts). All the as-deposited films have shown a preferential c-axis orientation associated with varying grain size as a function of Ts ranging from 100 to 600 °C. Current-voltage (I-V) characteristics of these films show Ohmic behavior over the entire Ts range studied. These films were subjected to annealing at 800 °C in air ambient for 4 h. The grain size was observed to increase after the annealing process for all the films deposited at different Ts. Interestingly, these annealed films show nonlinear variation of current with applied voltage, very similar to the one observed in doped ZnO varistors. The nonlinear parameters such as the asymmetric behavior of change in current on the polarity reversal of voltage, the plateau region, and the break down voltage are observed to depend on Ts. This nonlinear behavior can perhaps be explained on the basis of electronic conduction model proposed for the bulk, doped ZnO varistors. The role of insulating intergranular layers between the disoriented microcrystallites is expected to be similar to that played by insulating intergranular layers in the doped ZnO varistors. [ABSTRACT FROM AUTHOR]

Epitaxial thin films of La[sub 0.67]Ca[sub 0.33]MnO[sub 3] were implanted with 30 and 100 keV [sub 57]Fe ions at different fluence values to achieve a uniform implant distribution. The resistivity of the film increases as fluence increases, but the peak resistivity temperature T[sub p] does not change significantly for the as-implanted sample. Annealing of the implanted samples at 950°C allows recovery of the structural properties of the films and leads to interesting properties: increase of the peak resistivity and of the colossal magnetoresistance values, and decrease of T[sub p]. The decrease in T[sub p] is of ∼130 K, and the increase in resistivity is almost a factor of 28 as compared to the as-implanted sample. [ABSTRACT FROM AUTHOR]

Focuses on a study conducted on thin carbon films deposited on polycrystalline tungsten foil as well as field ion microscope tips by laser-ion deposition in a high-vacuum environment. Structural characterization of the films; Photoelectron spectra of the deposited films; Analysis of Sequence of layers on deposited tungsten.

Focuses on an optical spectroscopy study which examined the role of aluminum in laser ablated YBa[sub2]Cu[sub3]O[sub7-δ] thin films. Advantages of pulsed laser deposition; Analysis of the spectra for aluminum oxide transitions; Generation of aluminum oxide films.

Epitaxial films of La[sub 2/3]Ca[sub 1/3]MnO[sub 3] were successively implanted with 100 and 200 keV silver ions at fluences of 4.5x10[sup 15] and 1x10[sup 16] ions/cm[sup 2], respectively, to achieve a fairly uniform implant distribution. The as-implanted films are insulating and do not show a metal-insulator transition. Postimplantation annealing at 950 °C shows a recovery of the high structural quality of the films, along with an increase in the metal-insulator transition temperature (T[sub p]), magnetoresistance, and the peak temperature coefficient of resistance (TCR) at the transition. The peak TCR of 23% for manganite films is clearly significant for bolometric applications. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Dynamic scaling behavior of the droplet size distribution in the coalescence regime for growth by pulsed laser deposition is studied experimentally and by computer simulation, and the same is compared with that for continuous vapor deposition. The scaling exponent for pulsed deposition is found to be (1.2 +/- 0.1), which is significantly lower as compared to that for continuous deposition (1.6 +/- 0.1). Simulations reveal that this dramatic difference can be traced to the large fraction of multiple droplet coalescence under pulsed vapor delivery. A possible role of the differing diffusion fields in the two cases is also suggested.