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Due to an increase in global nuclear security issues, there need to be improvements in human resources and security measures. The Republic of Indonesia is an archipelago country, which makes surveilling for nuclear security threats complicated. Recent radioactive material smuggling incidents proved that Indonesian police and security officers’ knowledge in nuclear security has been challenged and must be improved. In response, Universitas Gadjah Mada’s Nuclear Engineering Program composed a three-day pilot training program for local police and UGM's security officers in 2018. The objective of the training was to improve their capabilities in dealing with nuclear security issues around where they work and serve. Training materials were designed to introduce nuclear technology and provide the basic skills of handling nuclear security matters. The training was divided into 12 sessions, based on the needs stated by the Special Region of Yogyakarta's police chief. Lessons were delivered through traditional teaching, table-top exercises, exercises, and discussion. Fifteen-question pre-tests and post-tests were conducted to assess the officers’ knowledge of the training materials and the benefits of being trained. Based on the tests, we concluded that the participants’ understanding of nuclear security had improved. This increase in understanding was because the training materials fit their job needs, presented in various methods, and the participants’ awareness grew. It led to an increase in their awareness for securing the facilities utilizing radioactive sources in the Yogyakarta area. They said that the number of trainees in this event still does not meet the number of facilities that have to be secured. Therefore, the training should be carried out again and can be improved based on the participants' feedback. Furthermore, this training could be expanded and applied to the whole country.

Activated zinc sulfide (ZnS) is a semiconductor material which able to emit photon in the form of visible light when expose to external energy. The capability of activated ZnS, mainly doped with silver (Ag) and copper (Cu), to convert radiation become light to make it potentially applicable as the radioluminescent thin film for alphaphotovoltaic-type nuclear battery. One of the important specifications of the radioluminescence layer that influences the fluorescence efficiency is the thickness. This work presents a study on the thickness optimization for ZnS:Ag:Cu as the radioluminescent film for alpha particles using Monte Carlo model. Simulation to study alpha particles’ energy deposited by using Stopping and Range of Ions in Matter/TRansport of Ions in Matter (SRIM/TRIM) code. The model examined the transport of 5.485 MeV alpha particles emitted by to determine the best thickness based on energy deposition depth. Based on TRIM module simulation, the optimal thickness for radioluminescence film is approximately 19-22 µm. Most energy from 5.485 MeV alpha particles is deposited in 18.92 µm depth activated zinc sulfide. The results from SRIM/TRIM model then compare with analytical calculation using Bragg-Kleman rule. The alpha particles stop at 22 µm from the SRIM/TRIM simulation while using Bragg-Kleman formula the alpha particles stop at 23.51 µm.

Barium Strontium Titanate (BST) film has been successfully produced as a light sensor. The BST film was made by CSD method by reacting barium acetate, strontium acetate and titanium isoprop...

Isotopes of 137Cs are one of the radioactive wastes that produce a large number of yields (about 6.2% of fission products for nuclear reactors). 137Cs could have negative impacts on the environment when released from a nuclear reactor such as environmental hazards and genetic mutations for living beings. Metal-Organic Frameworks (MOF) is a porous material that has the potential to clean up 137Cs waste. This study aims to determine the effect of the initial adsorbate concentration and the temperature of the mixture of the adsorbent and adsorbate solution during the adsorption process. Adsorption was carried out using Zn4O(BDC)3 as an adsorbent and stable 133Cs as a simulation adsorbate. Adsorption testing was carried out using Atomic Absorption Spectrometry (AAS) to determine the concentration in the sample. Adsorption was carried out by varying the initial concentration of the adsorbate (C0) by 25 mg/L, 50 mg/L, and 100 mg/L and the variation in the adsorption temperature of 27°C, 35°C, and 45°C. MOF characterization testing was carried out by SEM, XRD, FTIR, and BET. The result of the characterization shows that ZN4O(BDC)3 produced was appropriate compared to previous research. However, the surface area of the Zn4O(BDC)3 was below the average of usual Zn4O(BDC)3 (20,8006 m2/g compared to 2900 m2/g). The results show that the higher the initial concentration of the adsorbate, the more adsorbates are adsorbed. It's shown in samples with an initial concentration of 100 mg/L having a greater concentration of samples with initial concentrations of 25 mg/L and 50 mg/L. The effect of the temperature of the adsorbent and adsorbate mixture solution on adsorption showed fluctuating results so that conclusions could not be drawn.

Gas sensor based on nanostructured tin oxide (SnO2) and multi-walled carbon nanotube (MWCNT) composite material has successfully been synthesized. Reflux method was used to produce SnO2-MWCNT powder with various ratio 1:0, 4:1, 2:1, 1:1 and 0:1. The XRD result shows that the synthesized material comprises of the combination of carbon elements (MWCNT) and SnO2 of the crystalite cassiterite phase. BET analysis shows that MWCNT particles increase the specific surface area of SnO2 particles. SEM images show the morphology of the SnO2 nanoparticle composite attached to the MWCNT wall with a diameter of 40-60 nm and dispersed around it. Gas sensor testing was carried out at room temperature, 50, 100, 150, 200, 250, 300, and 350°C. All sensor samples were exposed to 30 ppm CO gas for 15 minutes. . It was found that sample with 1:0 ratio gives the best response with 98.91% at 350°C. CO gas tests have also been carried out at various concentration 10, 30, 50 and 70 ppm to 4:1 SnO2-MWCNT sample at 150°C. The higher the CO gas concentration, the greater the response. SnO2-MWCNT with 4:1 ratio at 50°C has the fastest response time of 10 s and the fastest recovery time of 3 s.

This paper presents the research on the growth of ZnS:Ag:Cu thin film on a glass substrate as a radio-luminescent material. The SRIM/TRIM software is used to determine the optimum thickness based on an energy deposition depth of 5.485 MeV Am 241 alpha radiation source on ZnS:Ag:Cu material. To increase the adhesive strength of the coating, initially, the glass substrate is etched using a plasma glow discharged at 280°C for 15 minutes. Multiple coatings of ZnS:Ag:Cu were etched on the glass substrate; this was carried out using a thermal evaporation technique to achieve the optimal thickness (based on SRIM/TRIM simulation). The thin film thickness was observed using a scanning electron microscope (SEM). The optical properties of the un-etched, etched glass substrate and thin-film were characterized using UV-Vis spectrometer. Based on SRIM/TRIM simulation, the optimal thickness is 22 mm which can be achieved by coating three times. From optical properties of ZnS:Ag:Cu thin film and after being analysed using Taue plot method, it is found that the energy gap of ZnS:Ag:Cu thin film is 2.48 eV. It can be concluded that the addition of Ag and Cu doped decrease the energy gap of ZnS (3.66 eV).

This study aimed to analyze the influence of service quality, corporate image, and customer relationship marketing on customer satisfaction and customer loyalty. The population consisted of 180 bank customers in Malang city. For the analysis of Structural Equation Model (SEM) came into use. The results showed that service quality, corporate image, and customer relationship marketing influence on customer satisfaction, and service quality, corporate image, and customer relationship marketing influence on customer loyalty. Moreover, customer satisfaction effects on customer loyalty. Customer satisfaction mediated the effect of service quality, corporate image, and customer relationship marketing on customer loyalty.

One of the procedures to handle liquid radioactive waste is by filtration process. To do this process, suitable filter should be used because of radioactive nature of the waste. Ceramic filter is one of the suitable filters that could be used for this purpose. This paper will discuss about producing ceramic filter from local clay and test its performance. Performance of the filter is given by its flux, compressive strength, Decontamination Factor (DF) and adsorption efficiency. The results show that there are almost no effects of casting pressure on both flux and compressive strength of ceramic filter, but zeolite addition produces different effect. The higher concentration of zeolite will decrease the filter flux and increase filter compressive strength. The optimal composition from this research is 70% w/o clay-25% w/o zeolite-5% w/o charcoal. It has adsorption efficiency (60.36) and Decontamination Factor (2.52). Besides, Sr concentration after filtration is still higher than environmental standard for Sr-90 and more studies are still needed.

Nanofibers have been demonstrated to be highly effective for drug delivery applications. Although magnetic nanoparticles (MNPs) have been potentially added to nanofibers for improved drug release stimulation, the effect has been limited. In this study, a magnetic nanofiber membrane composed of cellulose acetate (CA), collagen (COL), and MnFe2O4 MNPs was prepared by electrospinning. Naproxen (NAP) drug was deposited on the nanofibers, and the drug release mechanism and effect of the MNPs on the stimulated NAP release were investigated. The electrical conductivity of the dope solution strongly affected the nanofiber characteristics. Moreover, the MTT cytotoxicity assay proved that CA-COL, CA-COL-NAP, and CA-COL-NAP-MNP nanofibers had low toxicity, as the cell viability was >80%. The NAP release mechanism was determined using zero-order, first-order, Higuchi, and Korsmeyer-Peppas kinetics models. According to the dissolution results, for all nanofibers, the NAP release followed the Korsmeyer-Peppas kinetics model, and the transport mechanism was Fickian diffusion. A high MNP concentration and neutral pH condition were conducive to NAP release.

Back Surface Field (BSF) has been used as one of means to enhance solar cell performance by reducing surface recombination velocity (SRV). One of methods to produce BSF is by introducing highly doped layer on rear surface of the wafer. Depending on the type of the dopant in wafer, the BSF layer could be either p+ or n+. This research aims to compare the performance of BSF layer both in p-type and n-type wafer in order to understand the effect of BSF on both wafer types. Monociystalline silicon wafer with thickness of 300 μm. area of 1 cm2, bulk doping level NB = 1.5×1016/cm3 both for p-type wafer and n-type wafer are used. Both wafer then converted into solar cell by adding emitter layer with concentration NE =7.5×1018/cm3 both for p-type wafer and n-type wafer. Doping profile that is used for emitter layer is following complementary error function (erfc) distribution profile. BSF concentration is varied from 1×1017/cm3 to 1×1020/cm3 for each of the cell. Solar cell performance is tested under standard condition, with AM1.5G spectrum at 1000 W/m2. Its output is measured based on its open circuit voltage (Voc). short circuit current density (JSC), efficiency (η). and fill factor (FF). The result shows that the value of VOC is relatively constant along the range of BSF concentration, which is 0.694 V – 0.702 V. The same pattern is also observed in FF value which is between 0.828 – 0.831. On the other hand, value of JSC and efficiency will drop against the increase of BSF concentration. Highest JSC which is 0.033 A/cm2 and highest efficiency which is 18.6% is achieved when BSF concentration is slightly higher than bulk doping level. The best efficiency can be produced when BSF concentration is around 1×1017cm-3.. This result confirms that surface recombination velocity has been reduced due to the increase in cell’s short circuit current density and its efficiency. In general both p-type and n-type wafer will produce higher efficiency when BSF is applied. However, the increase is larger in p-type wafer than in n-type wafer. Better performance for solar cell is achieved when BSF concentration is slightly higher that bulk doping level because at very high BSF concentration the cell’s efficiency will be decreased.

In this work, (002) oriented ZnO thin film for carbon monoxide (CO) gas sensing application has been synthesized on the glass substrate using diethanolamine (DEA) as a chelating agent by two-step process. First, the seed layers were formed at a glass substrate using dip coating method, and second, ZnO nanostructure was grown using Chemical Bath Deposition (CBD) at low temperature. The structural and orientation of ZnO films were confirmed using x-ray Diffraction (XRD) while their morphologies and size were analyzed using Scanning Electron Microscopy (SEM). Diffraction pattern showed that the resulting film has wurtzite structure and an extremely sharp (002) peak was found, indicated that the ZnO nanostructure was growth along (002) orientation. The SEM image showed that the (002) oriented ZnO has hexagonal shape nanorods which vertically aligned. It was found that the diameter and length of ZnO nanorods were 71–96 nm and 666 nm, respectively. The gas sensing performance was investigated at various temperatures (160 °C, 200 °C, 250 °C, and 300 °C) and CO gas concentrations (10, 30, 50, 70 and 90 ppm). The results showed that the highest response, 53.25% was obtained at 200 °C toward 90 ppm CO gas. The response and CO gas concentration have a good linearity relationship which indicated that the (002) oriented ZnO has high potential for high sensitive CO gas sensor.

Indonesia has planned to erect Nuclear Power Plant for along time, but the government always postponed the plan due to the presence of anti-nuclear group that decreases the public acceptance. In addition, the public knowledge on nuclear technology is still low, since they only get in the last month before finish their study in high school. The socialization of nuclear technology done by government body could not significantly increase the public acceptance, since the knowledge and confidence on nuclear technology among the government employee is also low. The recent issue regarding to nuclear security give a new opportunity in socializing strategy. Department of Nuclear Engineering and Engineering Physics Universitas Gadjah Mada (UGM) as the only one university in Indonesia offering nuclear engineering education had conducted several nuclear security training for specific people who had been not targeted in previous socialization programs. The training done in collaboration with National Nuclear Energy Regulatory Body (BAPETEN) of Indonesia was conducted in Batam, Surabaya and Jakarta. Almost 20 people coming from police department, national coast guard, custom agency, etc attended in the training. Training materials consist of introduction on nuclear technology, introduction on nuclear security, physical protection system, radiation detection, transport security, etc. Pre-test and post-test were done to know their improvement. This was first time for most of participants to get nuclear technology knowledge. Based on the survey their knowledge was significantly improved. They felt that the training was valuable for them to know the benefit and risk of nuclear technology. We believe that it could increase the public participant and acceptance on utilizing nuclear technology in Indonesia.

Efisiensi sel surya dapat ditingkatkan dengan mengurangi rekombinasi pada permukaan belakang dari sel surya. Salah satu strategi yang dapat digunakan untuk mengurangi rekombinasi pada permukaan belakang adalah dengan mengurangi konsentrasi pembawa muatan minoritas di bagian permukaan belakang sel surya. Kondisi ini dapat dicapai dengan membuat lapisan boron p+ pada permukaan belakang sel surya yang memiliki konsentrasi lebih tinggi daripada basis dan memiliki tipe doping yang sama, dikenal sebagai lapisan boron -back surface field (B-BSF). Saat ini berdasarkan kecenderungan eksperimental, didapatkan bahwa peningkatan konsentrasi doping dan ketebalan lapisan B-BSF akan meningkatkan efisiensi sel surya. Akan tetapi, pada proses fabrikasi B-BSF eksperimental, ditemukan bahwa meningkatkan ketebalan lapisan BSF sangat sulit dan meningkatkan biaya. Oleh karena itu diperlukan studi untuk menganalisis sampai batas mana usaha untuk meningkatkan ketebalan lapisan BSF secara eksperimental dapat memberikan peningkatan nilai efisiensi yang memadai untuk digunakan pada industri sel surya di masa depan. Pada penelitian ini telah dilakukan analisis secara simulasi, pengaruh ketebalan dan konsentrasi lapisan boron BSF terhadap efisiensi pada sel surya berbasis wafer silikon monokristal. Simulasi dilakukan menggunakan perangkat lunak PC1D. Simulasi dilakukan pada wafer 300 mikron dengan doping dasar tipe-p 1,50x1016/cm3 dan emitter tipe-n dengan ketebalan 1,56 mikron dan konsentrasi doping 7,5x1018/cm3 yang memiliki efisiensi 16,30%.Hasil simulasi menunjukkan bahwa secara umum semakin tebal lapisan boron p+ dan semakin tinggi konsentrasi dopingnya, efisiensinya akan semakin meningkat. Pengecualian terdapat pada ketebalan lapisan diatas 220 mikron dan konsentrasi diatas 1,26x1019/cm3. Hasil ini sesuai dengan kecenderungan eksperimental dan memprediksikan bahwa kecenderungan ini akan berlanjut sampai nilai ketebalan lapisan BSF yang sangat ekstrim. Akan tetapi ditemukan bahwa laju peningkatan efisiensi terhadap peningkatan ketebalan lapisan BSF mengalami penurunan secara signifikan setelah ditingkatkan melebihi ketebalan 20 mikron. Selanjutnya optimasi dilakukan untuk memaksimalkan efisiensi sel surya terhadap variasi dari ketebalan dan konsentrasi. Ditetapkan tiga pembatas yakni konsentrasi doping, ketebalan lapisan dan peningkatan efisiensi marjinal terhadap peningkatan ketebalan lapisan. Untuk konsentrasi doping NBSF dibatasi 1017/cm3≤NBSF≤1020/cm3 dan ketebalan lapisan WBSF dibatasi sampai 20 mikron. Sebagai pertimbangan kompromi antara usaha untuk peningkatan efisiensi dan kemudahan dalam pembuatan lapisan BSF, ditetapkan bahwa nilai optimum harus memberikan peningkatan efisiensi marjinal terhadap peningkatan ketebalan lapisan lebih besar atau sama dengan 0,01%/mikron. Optimasi matematis dilakukan dengan metode brute force search. Berdasarkan hasil optimasi, direkomendasikan untuk meningkatkan ketebalan lapisan boron hingga 20 mikron dan meningkatkan konsentrasi sampai 3,40x1018/cm3. Apabila rekomendasi desain dapat dipenuhi, efisiensi sel surya dengan boron p+ dapat ditingkatkan hingga 17,58%.