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"Penelitian ini bertujuan untuk mengeksplorasi sifat antikorosi dan antibakteri pada implan gigi berbasis SS 316L yang dilapisi komposit perak-hidroksiapatit/multi-walled carbon nanotubes (Ag-HA/MWCNT) menggunakan teknik elektroforesis deposisi (EPD). Proses EPD dilakukan pada tegangan 30V dan 60V selama 20 menit dengan menggunakan suspensi etanol dan metanol, serta variasi konsentrasi Ag sebesar 1, 3, dan 5 wt%. Hasil penelitian menunjukkan terbentuknya vibrasi regangan P-O dari gugus fosfat (PO4³⁻) di semua sampel, yang mengindikasikan keberhasilan deposisi komposit Ag-HA/MWCNT. Morfologi lapisan Ag-HA/MWCNT memperlihatkan partikel yang tersusun secara globular, semakin meluas dengan peningkatan konsentrasi Ag, dan membentuk entitas lapisan yang melekat baik pada permukaan SS 316L. Tegangan 60V pada EPD menghasilkan deposisi yang lebih seragam dibandingkan dengan tegangan 30V. Pelarut metanol sebagai suspensi pada metode EPD menghasilkan deposisi Ag-HA/MWCNT yang seragam dan menutupi seluruh permukaan implant gigi SS 316L. Analisis komposisi mengkonfirmasi keberadaan unsur kalsium, fosfor, karbon, perak, dan oksigen pada permukaan lapisan. Uji efisiensi korosi dalam simulasi cairan tubuh menunjukkan peningkatan resistansi polarisasi dengan penurunan densitas arus (icorr) menjadi 0,096 μA/cm², dan laju korosi yang rendah sebesar 3.32 x 10⁻5 mm/y, seiring dengan peningkatan konsentrasi Ag. Selain itu, peningkatan zona inhibisi terhadap bakteri E. coli dari 9 mm menjadi 11 mm ditemukan pada lapisan dengan konsentrasi Ag 5 wt%. Oleh karena itu, dapat disimpulkan bahwa deposisi Ag-HA/MWCNT 5 wt% pada permukaan implan gigi berbasis SS 316L menunjukkan sifat antikorosi yang tinggi dan sifat antibakterial yang kuat, sehingga berpotensi digunakan sebagai alternatif material untuk implan gigi.

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This study investigates the corrosion resistance and antibacterial properties of silver-hydroxyapatite/multi-walled carbon nanotube (Ag-HA/MWCNT) composite-coated SS 316L dental implants fabricated using electrophoretic deposition (EPD).The EPD process was conducted at voltages of 30V and 60V for 20 minutes using ethanol and methanol suspensions and Ag concentrations of 1, 3, and 5 wt%. Results confirmed the successful deposition of Ag-HA/MWCNT composites, as evidenced by the presence of P-O stretching vibrations from phosphate groups (PO4³⁻) in all samples. The morphology of the Ag-HA/MWCNT coatings revealed globular particles that became more extensive with increasing Ag concentration, forming a well-adherent layer on the SS 316L surface. EPD at 60V yielded more uniform deposition compared to 30V. Methanol suspension resulted in uniform Ag-HA/MWCNT deposition covering the entire SS 316L dental implant surface. Compositional analysis confirmed the presence of calcium, phosphorus, carbon, silver, and oxygen on the coating surface. Corrosion efficiency analysis in simulated body fluid demonstrated an increase in polarization resistance and a decrease in current density (icorr) to 0.096 μA/cm², indicating a low corrosion rate of 3.32 x 10⁻⁵ mm/y, with increasing Ag concentration. Additionally, an enhanced inhibition zone against E. coli bacteria, from 9 mm to 11 mm, was observed for the 5 wt% Ag-coated layer. These findings suggest that 5 wt% Ag-HA/MWCNT deposition on SS 316L dental implants exhibits superior corrosion resistance and strong antibacterial properties, making it a promising alternative material for dental implant applications."

"Coal is the main commodity required by various countries as a substitute for petroleum as an energy source. This study aims to look at the competitiveness of Indonesian coal exports and the development of Indonesian coal in eight countries of export destination and want to study the effect of the ratio of the price of coal, the export destination country's GDP, exchange rate, and the value of RCA against Indonesian coal exports. Export destinations in this study are China, India, Japan, South Korea, Hong Kong, Thailand, Malaysia, and the Philippines and the study period is 2002-2012.. This study uses RCA index, EPD, and IIT and panel data regression analysis. The results show that in general the development of export coal to eight destination countries has increased. RCA results show Indonesian coal generally has a comparative advantage in the eight countries of export destination. Based on EPD index, almost in all destination countries except Hong Kong, Indonesia coal competitive position is a rising star. Based on the method of IIT, the nature of Indonesia's trade with all destination countries except Hong Kong are weak integration that is no integration. Variables that affect the volume of coal exports is real GDP export destinations, the real exchange rate of export destinations, and RCA. Meanwhile, the Indonesian coal price ratio does not significantly affect the volume of Australian coal exports."

"Penelitian ini melakukan modifikasi pembuangan paket EPD pada TCP melalui UBR dan menganalisa performansi jaringan berupa efisiensi jaringan dan indeks fairness. Modifikasi dilakukan dengan mengubah metoda pembuangan paket EPD, karena pada metoda EPD pencapaian indeks fairness-nya belum optimal, dimana belum mempertimbangkan tingkat pemakaian buffer oleh setiap VC. Untuk meningkatkan indeks fairness, penelitian ini mempertimbangkan tingkat pemakaian buffer oleh setiap VC. Dengan menggunakan MST ATMIHFC Network Simulator; efisiensi jaringan dan indeks fairness dihitung dan dianalisa pada 6 skenario simulasi dengan variasi ukuran buffer, threshold buffer, ukuran MSS, jumlah source, kecepatan link TCP dan kecepatan link antar switch. Hasil simulasi menunjukkan peningkatan performansi dan penggunaan pembuangan paket EPD ke modifikasi EPD. Pada simulasi variasi buffer, efisiensi naik 18 % dan indeks fairness naik 31 %. Pada simulasi variasi threshold, efisiensi naik 27 % dan indeks fairness naik 30 %. Pada simulasi variasi MSS, efisiensi naik 21% dan indeks fairness naik 4 %. Pada simulasi variasi jumlah source, efisiensi naik 42 % dan indeks fairness naik 20 %. Pada simulasi variasi link switch, efisiensi naik i3 % dan indeks fairness naik 11%. Pada simulasi variasi link TCP , efisiensi naik 21% dan indeks fairness naik 6 %.

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This thesis proposes a modification in EPD method on TCP over UBR and analyzes the performance of network for fairness index and efficiency. Modification is done by considering the usage of buffer for every VC, because fairness index is not optimal, where this method not checks level of usage of buffer for every VC. Using KIST ATMJFIFC Network Simulator, the efficiency and fairness index are calculated and analyzed in 6 scenarios of simulations with the various size of buffer, threshold, MSS, amount of the source, speed of TCP link and speed of switch link.

The simulation result shows that the efficiency and fairness index increase by using EPD modification and give performance improvement compared to EPD method. In various buffer simulation, improvement 18 % on efficiency and 31 % on fairness index. In various threshold simulation, improvement 27 % on efficiency and 30 % on fairness index. In various size of MSS simulation, improvement 21 % on efficiency and 4 % on fairness index. In various amount of the source simulation, improvement 42 % on efficiency and 20 % on fairness index. In various speed of switch link simulation, improvement 13 % on efficiency and 11 % on fairness index. In various speed of TCP link simulation, improvement 21 %n on efficiency and 6 % on fairness index."