Hasil Pencarian  ::  Simpan CSV :: Kembali

Abstrak :
ABSTRACT
One of the processes requiring HPC environments is Molecular Dynamics ( MD ) . In tropical countries, the MD process is very important in the preparation of virtual screening experiments for anti-malaria search. Previous works on the virtual screening project for anti-malaria search conducted by WISDOM project uses grid infrastructure with 1,700 CPUs of various infrastructure provided in 15 countries [13]. In silico anti malaria compounds searching from Indonesian medical plants using virtual screening methods are urgently required. This can reduce the cost and time required compared to the direct searching or examining each compound by in vitro and in vivo which will spend a lot of time and expense . However, the use of thousands of processors is difficult for the researchers with limited resources in developing countries such as Indonesia. Our of previous studies using MD with GROMACS shows the improvement of the simulation time using Cluster. But that is not the case for some of our previous works with AMBER on Cluster where we did not obtain significant speed up. However, our previous works running GROMACS on GPUs provided significant speed up about 12 times faster than that run on Cluster. In this study , we build a GPU -based computing environment and have some MD simulation with AMBER. We used several computing environments such as cluster with 16 cores , GPU Geforce GTX 465 , GTX 470 , GTX 560 , GTX 680 , and GTX 780 . In addition to PfENR ( Plasmodium falciparum Enoyl acyl Carrier Protein Reductase ) enzyme , as benchmark we also conducted MD experiments on Myoglobin protein , Dihydrofolate reductase (DHFR) protein, and Ras - Raf protein . All experimental results showed that the slowest MD processes occurred on Cluster, followed in increasing order by GTX 560, GTX 465, GTX 470, GTX 680 and GTX 780. While the GPU speed up relative to cluster is about 24 , 26 , 32 , 24 , 77 and 101, respectively.

Abstrak :
ABSTRACT
Molecular Dynamics (MD) is one of processes that requires High Performance Computing environments to complete its jobs. In the preparation of virtual screening experiments, MD is one of the important processes particularly for tropical countries in searching for anti-Malaria drugs. The search for anti-Malaria has previously conducted, for example by WISDOM project utilizing 1,700 CPUS. This computing infrastructure will be one of the limitation for country like Indonesia that also needs in silico anti malaria compounds searching from the country medical plants. Thus finding suitable and affordable computing environment is very important. Our previous works showed that our dedicated Cluster computing power with 16 cores performance better than those using fewer cores, however the GPU GTX family computing power is much better. In this study, we investigate further our previous experiment in finding more suitable computing environment on much better hardware specification of non dedicated Cluster computing and GPU Tesla. We used two computing environments, the first one is Barrine HPC Cluster of The University of Queensland which has 384 compute nodes with 3144 computing cores. The second one is Delta Future Grid GPU Cluster which has 16 computing nodes with 192 computing cores, each nodes equipped with 2 NVIDIA Tesla C2070 GPU (448 cores). The results show that running the experiment on a dedicated computing power is much better than that on non dedicated ones, and the GPU performance is still much better than that of Cluster.

Abstrak :
The invention of graphical processing units (GPUs) has significantly improved the speed of long processes used in molecular dynamics (MD) to search for drug candidates to treat diseases, such as malaria. Previous work using a single GTX GPU showed considerable improvement compared to GPUs run in a cluster environment. In the current work, AMBER and dual GTX 780 and 970 GPUs were used to run an MD simulation on the Plasmodium falciparum enoyl-acyl carrier protein reductase enzyme; the results showed that performance was improved, particularly for molecules with a large number of atoms using single GPU.

Abstrak :
Masalah yang dihadapi pada terminal regasifikasi skala kecil ini adalah kondisi operasi yang unsteady. Dikarenakan terdapat 2 kondisi, yaitu pada saat unloading LNG dari kapal LNG dan juga pada saat holding karena operasi on-off dari vaporizer berjenis AAV (Ambient Air Vaporizer) yang disebabkan terjadinya frosting. Dalam penelitian ini, dilakukan simulasi dinamik dari terminal regasifikasi skala kecil dengan pengendalian dalam perangkat lunak UniSim. Jika simulasi dilakukan tanpa pengendalian, menghasilkan laju alir yang menyimpang 14% dari seharusnya, dan setelah 6 jam suhu gas keluaran kurang dari 2,5°C yang artinya output tidak dapat memenuhi requirement pembangkit. Pengendali yang digunakan adalah pengendali tipe digital on-off  untuk unloading dan switch AAV dan PI untuk pengendalian laju alir LNG. Pengendali digital on-off pompa diatur untuk menghentikan unloading saat LNG di carrier bersisa 10%, sementara AAV akan diset untuk melakukan aksi switch AAV saat suhu gas keluaran mencapai 3°C. Untuk pengendali PI didapat parameter pengendali dengan nilai Kc = 0,00638 dan Ti = 0,00043. Waktu maksimal operasi 1 buah AAV adalah 7 jam 30 menit sebelum akhirnya akan dilakukan switch. Setelah pengendalian, spesifikasi gas keluaran terminal mampu untuk memenuhi requirement pembangkit yaitu laju alir molar 6,53 MMSCFD dan suhu gas minimum 2,5°C.

---

The problem encountered at this regasification terminal is unsteady operating conditions. Because of unloading LNG from a carrier and holding that involve on-off operation from AAV (Ambient Air Vaporizer) caused by frosting. In this study, a dynamic simulation of small-scale regasification terminal with controls UniSim carried out. If the simulation carries without control, it produces a flow rate that deviates 14% from what it should be, and after 6 hours of operation, the output temperature less than 2,5°C, which means cannot meet generator requirements. The controllers used in this case is digital on-off type controller for unloading and switch AAV and PI type controller to control LNG flowrate. For digital on-off controller, the controller is set to stop unloading when remaining LNG in the carrier is 10%, meanwhile AAV will be set to act on the switch when output temperature reach 3°C . For PI controllers, the control parameters with Kc = 0,00638 and Ti = 0,00043. The maximum operating time for 1 AAV is 7 hours 30 minutes before it will be switched. After controlling, the gas specifications from terminal able to meet the generator requirements, molar flow rate 6,53 MMSCFD and minimum gas temperature 2,5°C.

Abstrak :
Penelitian ini dilakukan perancangan kendaraan roda tiga listrik berkonfigurasi tadpole dengan sistem kontrol aktif kemiringan kendaraan pada dua roda depan saat berbelok. Pemodelan matematis dilakukan berdasarkan disain yang telah dihasilkan. Simulasi dinamik stabilitas dilakukan untuk menghitung kemiringan kendaraan yang diperlukan agar mencegah kendaraan terguling saat berbelok. Penerapan sudut kemiringan bertujuan untuk menyeimbangkan gaya sentrifugal yang dapat menyebabkan kendaraan terguling. Model kontak antara ban kendaraan dan permukaan jalan adalah model dugoff. Parameter simulasi diperoleh dari desain 3D menggunakan perangkat lunak Autodesk Inventor dan pengukuran aktual. Simulasi dinamis dilakukan melalui Simulink MATLAB online, sedangkan kontrol aktif kemiringan kendaraan diimplementasi menggunakan perangkat lunak Arduino IDE. Hasil penelitian ini menunjukan bahwa penerapan sistem kontrol aktif kemiringan berhasil mengurangi percepatan lateral kendaraan, meningkatkan kenyamanan penumpang, dan pada kecepatan kritis, terjadi peningkatan signifikan pada sudut kemudi 10 derajat dan 20 derajat, masing-masing sebesar 72.48% dan 74.22%. ......In this research, the design of a three-wheeled electric vehicle with a tadpole configuration and an active tilt control system on the two front wheels during turning is conducted. Mathematical modeling is carried out based on the generated design. Dynamic stability simulations are performed to calculate the required vehicle tilt to prevent rollovers during turns. The implementation of tilt angles aims to balance centrifugal forces that may lead to vehicle rollovers. The contact model between the vehicle tires and the road surface is based on the dugoff model. Simulation parameters are obtained from the 3D design using Autodesk Inventor software and actual measurements. Dynamic simulations are conducted through online Simulink MATLAB, while the active tilt control system is implemented using Arduino IDE software. The research results indicate that the implementation of the active tilt control system successfully reduces lateral acceleration of the vehicle, enhances passenger comfort, and at critical speeds, there is a significant increase in the critical speed of the vehicle at steering angles of 10 degree and 20 degree, by 72.48% and 74.22%, respectively.

Abstrak :
Pelabuhan Tanjung Priok dapat dikatakan sebagai salah satu Pelabuhan tersibuk di Indonesia, tetapi jika dibandingkan Pelabuhan Tanjung Priok masih kalah saing dengan Pelabuhan Internasional lain. Salah satu faktor adalah cukup tingginya nilai rata-rata waktu tunggu per kapal tiap tahunnya, berdasarkan kondisi tersebut perlu dilakukan sebuah penelitian, terkait dengan waktu tunggu kapal dan juga faktor-faktor yang mempengaruhinya. Faktor-faktor tersebut adalah jumlah tambatan di dermaga, Jumlah Penggunaan Crane serta Kapasitas Maksimal per Cranenya, Pelayanan Pandu dan Tunda Kapal, serta Idle Time dan Not Operating Time selama Waktu Pelayanan Kapal di Pelabuhan. Pada penelitian ini dilakukan analisis dan simulasi dengan menggunakan Metode Simulasi Sistem Dinamik yang akan dibandingkan dengan kondisi aktual di Pelabuhan hingga didapatkan hasil yang optimal. Pembuatan Model Sistem Dinamik menggunakan software Powersim, dan hasil nya di validasi dengan menggunakan Uji Two Sample T-Test. Dari penelitian ini didapatkan 2 usulan untuk perbaikan fasilitas pelabuhan, yaitu usulan jangka pendek dengan hasil nilai rata-rata waktu tunggu sebesar 0,34 jam atau 20 menit 9 detik, dan usulan jangka panjang dengan nilai rata-rata waktu tunggu sebesar 0,28 jam atau 16 menit 48 detik. ......Tanjung Priok Port can be said to be the one of the busiest ports in Indonesia, but when compared Tanjung Priok Port is still less competitive with other International Ports. One of the factor is the high average of waiting time per ship per year, based on the conditions it is necessary to conduct a study, related to the waiting time of the ship and also the factors that influence it. These factors are the number of berths at the dock, the amount of crane usage and the maximum capacity per crane, the scout and the delay services, as well as the idle time and not operating time during the port service time. In this research, analysis and simulation using the Dynamic System Simulation Method will be compared with the actual conditions at the port to obtain the optimal results. Making a Dynamic System Model by Powersim software, and the results are validated using the Two-sample T-Test. From this study, 2 proposals were obtained for the improvement of port facilities., namely short-term proposal wiht an average value of the waiting time is 0,34 hour or 20 minutes 9 second, and the long-term proposal with an average value of the waiting time is 0,28 hour or 16 minutes and 48 second.

Abstrak :
Freight transport plays a very important role in economic activities. However, in some cases, the local transportation authority often disregards its existence, including in parking management issues. This research is aimed at developing an optimization model for off-street parking space management that considers freight cars and passenger cars as two different entities. Optimization aims at minimizing the joint function of the parking index of freight cars and the parking index of passenger cars. Weighting is given to both parking indexes to represent the interest level of parking operator to both types of vehicles. Parking space of both vehicles is at any time is arranged in a dynamic manner based on the inflow and outflow rate of vehicles at previous times. The parking index is limited by the maximum parking index desired by the management. The proposed model is applied to the parking activity in Jatinegara Trade Center (JTC), Jakarta, and shows that the model solution provides a better parking index than the actual parking index (without optimization).

Abstrak :
Potensi gas hidrogen untuk diimplementasikan sebagai pembawa energi tanpa emisi sangat menjanjikan. Namun ada beberapa kendala yang harus dihadapi dalam pengimplementasiannya, yakni pengembangan teknologi penyimpanan gas hidrogen. Penyimpanan gas hidrogen dalam suatu adsorben karbon nanostruktur seperti carbon nanotube menjadi salah satu pilihan untuk dapat meningkatkan kapasitas penyimpanannya. Namun, banyaknya penelitian eksperimen yang tidak memberikan hasil yang reproducible menyebabkan perlunya ada pengembangan penelitian teoritis adsorpsi gas hidrogen dengan pendekatan termodinamika molekuler. Dengan kalkulasi struktur elektronik ab initio, energi potensial interaksi antar molekul gas hidrogen diestimasi sebesar 0,099 kcal/mol dan antara gas hidrogen dengan carbon nanotube diestimasi sebesar 1,057 - 1,142 kcal/mol. Energi potensial tersebut direpresentasikan ke dalam persamaan nilai parameter potensial klasik sebagai fungsi dari diameter carbon nanotube agar didapatkan model potensial yang paling presisi. Setelah mendapatkan nilai-nilai parameter potensial interaksinya, simulasi dinamika molekuler dilakukan dengan ensemble canonical untuk menganalisa adsorpsi gas hidrogen pada permukaan luar carbon nanotube. Dari hasil pengolahan data simulasi dinamika molekuler, didapatkan bahwa kalor isosterik berkurang dari 1,6 kcal/mol hingga menjadi 0,2 kcal/mol pada kondisi permukaan adsorben jenuh. Hasil ini cukup sesuai dengan hasil penelitian eksperimental literatur lainnya. ......The potency of hydrogen gas to be implemented as energy carrier with zero emission is very promising. Unfortunately, there are still crucial problems on its implementation, one of them is the development of hydrogen storage technology. Storing hydrogen gas on nanostructured carbon adsorbent could be an alternative to improve the storage capacity. However, the fact that there were so many experimental researches that couldn?t provide reproducible results creates a need to develop theoritical research on hydrogen gas adsorption on carbon nanotube using moleculer thermodynamics approach. Using ab initio electronic structure calculations, The interaction potential energies between hydrogen molecules were estimated to be 0.099 kcal/mol and between hydrogen molecule and the outer surface of carbon nanotube were estimated to be 1.057 - 1.142 kcal/mol. The potential energies then were represented into an equation of potential parameter as a function of carbon nanotube diameterin order to get the most precise interaction potential model. Molecular dynamics simulations were performed on canonical ensemble to analyze hydrogen gas adsorption on outer surface of carbon nanotube. From our calculations results, the isosteric heat of hydrogen physical adsorption on carbon nanotube were estimated to be 1.6 kcal/mol and decreased to 0.2 kcal/mol on saturated surface condition. This results are acceptable with some previous experimental researches results.

Abstrak :
Angkutan Barang berperan sangat penting dalam kegiatan ekonomi, namun jika tidak diatur dengan baik akan berdampak buruk terhadap lingkungan (kemacetan, polusi, kecelakaan dll). Tujuan penelitian adalah pengembangan model optimasi pengaturan ruang parkir off street dengan simulasi dinamis. Metode pengembangan model optimasi ruang parkir didasarkan pada pembagian ruang parkir atas ruang untuk angkutan barang dan ruang untuk non angkutan barang. Optimasi bertujuan meminimalkan nilai fungsi gabungan dari indek parkir angkutan barang dan indek parkir non angkutan barang. Pemberian bobot diberikan kepada indek parkir keduanya untuk merepresentasikan tingkat kepentingan terhadap kedua jenis kendaraan tersebut. Ruang parkir keduanya diatur secara dinamis tiap interval waktu tertentu, berdasarkan pada besarnya arus kendaraan masuk dan keluar pada waktu sebelumnya. Indek Parkir dibatasi oleh indek parkir maksimal yang diinginkan pengelola. Berdasarkan uji t terhadap varian nilai indek parkir gabungan, hasil aplikasi terhadap data parkir di Jatinegara Trade Center (JTC) memperlihatkan bahwa solusi model memberikan nilai indek parkir yang lebih baik dibandingkan nilai indek parkir aktual (tanpa optimasi).

---

Freight very important role in economic activity, but if are not well regulated will have a negative impact on the environment (congestion, pollution, accidents, etc.). The purpose of the research is the development of models optimization setting parking space off street with dynamic simulation. Development Method parking space optimization model is based on division of the parking space to freight and space for non-freight . Optimization aims to minimizing value of the combined function of freight parking index and nonfreight parking index. The weighting is given to parking index both to represent interest levels of both types of vehicles. Parking spaces are both set dynamically for each specified time interval, based on the magnitude of vehicle flow in and out at the previous time, where the parking index is restricted by parking index maximum who desired manager. Based t test to variance values parking index combined, the results of the application to data of parking in Djatinegara Trade Center (JTC) shows that model solution gives value parking index is better than value the actual parking index (without optimization).

Abstrak :
Angkutan Barang berperan sangat penting dalam kegiatan ekonomi, namun jika tidak diatur dengan baik akan berdampak buruk terhadap lingkungan (kemacetan, polusi, kecelakaan dll). Tujuan penelitian adalah pengembangan model optimasi pengaturan ruang parkir off street dengan simulasi dinamis. Metode pengembangan model optimasi ruang parkir didasarkan pada pembagian ruang parkir atas ruang untuk angkutan barang dan ruang untuk non angkutan barang. Optimasi bertujuan meminimalkan nilai fungsi gabungan dari indek parkir angkutan barang dan indek parkir non angkutan barang. Pemberian bobot diberikan kepada indek parkir keduanya untuk merepresentasikan tingkat kepentingan terhadap kedua jenis kendaraan tersebut. Ruang parkir keduanya diatur secara dinamis tiap interval waktu tertentu, berdasarkan pada besarnya arus kendaraan masuk dan keluar pada waktu sebelumnya. Indek Parkir dibatasi oleh indek parkir maksimal yang diinginkan pengelola. Berdasarkan uji t terhadap varian nilai indek parkir gabungan, hasil aplikasi terhadap data parkir di Jatinegara Trade Center (JTC) memperlihatkan bahwa solusi model memberikan nilai indek parkir yang lebih baik dibandingkan nilai indek parkir aktual (tanpa optimasi). ......Freight very important role in economic activity, but if are not well regulated will have a negative impact on the environment (congestion, pollution, accidents, etc.). The purpose of the research is the development of models optimization setting parking space off street with dynamic simulation. Development Method parking space optimization model is based on division of the parking space to freight and space for non-freight . Optimization aims to minimizing value of the combined function of freight parking index and nonfreight parking index. The weighting is given to parking index both to represent interest levels of both types of vehicles. Parking spaces are both set dynamically for each specified time interval, based on the magnitude of vehicle flow in and out at the previous time, where the parking index is restricted by parking index maximum who desired manager. Based t test to variance values parking index combined, the results of the application to data of parking in Djatinegara Trade Center (JTC) shows that model solution gives value parking index is better than value the actual parking index (without optimization).